Import wiredtiger: 27f8e047911ff31500fecf4ea760e688ec541b97 from branch mongodb-4.2

ref: a8a6314182..27f8e04791
for: 4.1.1

WT-3839       Document the undefined behavior when a range truncate overlaps with inserts
WT-3917       Enhance WT_CURSOR::reserve documentation around commit visibility
WT-4024       Fix a race between split and next/prev
WT-4067       Enhance LSM to not pin as much history in cache
WT-4111       Improve checkpoint scrubbing algorithm
WT-4125       Ensure that subsequent checkpoints with stable timestamp don't read too much
WT-4136       Add a new timing stress flag that yields during tree search
WT-4138       Add an option to timeout waiting for space in the cache
WT-4140       Cursor walk limits quick eviction page selection unnecessarily.
WT-4141       Enhance checkpoint with timestamps to unblock eviction sooner
WT-4145       Only include the checkpoint timestamp during checkpoints
WT-4146       Coverity 1393639, unused variable
WT-4152       Save return value for later comparison in transaction code

47 files changed, 1261 insertions, 938 deletions

diff --git a/src/third_party/wiredtiger/dist/api_data.py b/src/third_party/wiredtiger/dist/api_data.py
index 7d8a58c83bb..d29e9655fb3 100644
--- a/src/third_party/wiredtiger/dist/api_data.py
+++ b/src/third_party/wiredtiger/dist/api_data.py
@@ -417,6 +417,11 @@ connection_runtime_config = [
         maximum heap memory to allocate for the cache. A database should
         configure either \c cache_size or \c shared_cache but not both''',
         min='1MB', max='10TB'),
+    Config('cache_max_wait_ms', '0', r'''
+        the maximum number of milliseconds an application thread will wait
+        for space to be available in cache before giving up. Default will
+        wait forever''',
+        min=0),
     Config('cache_overhead', '8', r'''
         assume the heap allocator overhead is the specified percentage, and
         adjust the cache usage by that amount (for example, if there is 10GB
@@ -460,7 +465,7 @@ connection_runtime_config = [
                 vary depending on the current eviction load''',
                 min=1, max=20),
             ]),
-    Config('eviction_checkpoint_target', '5', r'''
+    Config('eviction_checkpoint_target', '1', r'''
         perform eviction at the beginning of checkpoints to bring the dirty
         content in cache to this level. It is a percentage of the cache size if
         the value is within the range of 0 to 100 or an absolute size when
@@ -585,7 +590,8 @@ connection_runtime_config = [
         type='list', undoc=True,
         choices=[
         'checkpoint_slow', 'lookaside_sweep_race', 'split_1', 'split_2',
-        'split_3', 'split_4', 'split_5', 'split_6', 'split_7']),
+        'split_3', 'split_4', 'split_5', 'split_6', 'split_7', 'split_8',
+        'split_9']),
     Config('verbose', '', r'''
         enable messages for various events. Options are given as a
         list, such as <code>"verbose=[evictserver,read]"</code>''',
diff --git a/src/third_party/wiredtiger/dist/stat_data.py b/src/third_party/wiredtiger/dist/stat_data.py
index 135c930b306..f4f8f61ee1e 100644
--- a/src/third_party/wiredtiger/dist/stat_data.py
+++ b/src/third_party/wiredtiger/dist/stat_data.py
@@ -279,6 +279,7 @@ connection_stats = [
     CacheStat('cache_read_lookaside_delay_checkpoint', 'pages read into cache with skipped lookaside entries needed later by checkpoint'),
     CacheStat('cache_read_lookaside_skipped', 'pages read into cache skipping older lookaside entries'),
     CacheStat('cache_read_overflow', 'overflow pages read into cache'),
+    CacheStat('cache_timed_out_ops', 'operations timed out waiting for space in cache'),
     CacheStat('cache_write', 'pages written from cache'),
     CacheStat('cache_write_app_count', 'application threads page write from cache to disk count'),
     CacheStat('cache_write_app_time', 'application threads page write from cache to disk time (usecs)'),
@@ -515,6 +516,7 @@ connection_stats = [
     TxnStat('txn_pinned_range', 'transaction range of IDs currently pinned', 'no_clear,no_scale'),
     TxnStat('txn_pinned_snapshot_range', 'transaction range of IDs currently pinned by named snapshots', 'no_clear,no_scale'),
     TxnStat('txn_pinned_timestamp', 'transaction range of timestamps currently pinned', 'no_clear,no_scale'),
+    TxnStat('txn_pinned_timestamp_checkpoint', 'transaction range of timestamps pinned by a checkpoint', 'no_clear,no_scale'),
     TxnStat('txn_pinned_timestamp_oldest', 'transaction range of timestamps pinned by the oldest timestamp', 'no_clear,no_scale'),
     TxnStat('txn_prepare', 'prepared transactions'),
     TxnStat('txn_prepare_active', 'prepared transactions currently active'),
diff --git a/src/third_party/wiredtiger/import.data b/src/third_party/wiredtiger/import.data
index 770e5ed12ec..1e72dbc56ae 100644
--- a/src/third_party/wiredtiger/import.data
+++ b/src/third_party/wiredtiger/import.data
@@ -1,6 +1,6 @@
 {
-    "commit": "a8a6314182ccf7dc6625b9c24891a355b07faa8e", 
+    "commit": "27f8e047911ff31500fecf4ea760e688ec541b97", 
     "github": "wiredtiger/wiredtiger.git", 
     "vendor": "wiredtiger", 
-    "branch": "mongodb-4.0"
+    "branch": "mongodb-4.2"
 }
diff --git a/src/third_party/wiredtiger/src/bloom/bloom.c b/src/third_party/wiredtiger/src/bloom/bloom.c
index cf4743009ee..d506af89ab7 100644
--- a/src/third_party/wiredtiger/src/bloom/bloom.c
+++ b/src/third_party/wiredtiger/src/bloom/bloom.c
@@ -302,7 +302,16 @@ __wt_bloom_hash_get(WT_BLOOM *bloom, WT_BLOOM_HASH *bhash)
 err:	if (c != NULL)
 		WT_TRET(c->reset(c));
 
-	/* Don't return WT_NOTFOUND from a failed cursor open or search. */
+	/*
+	 * Error handling from this function is complex. A search in the
+	 * backing bit field should never return WT_NOTFOUND - so translate
+	 * that into a different error code and report an error. If we got a
+	 * WT_ROLLBACK it may be because there is a lot of cache pressure and
+	 * the transaction is being killed - don't report an error message in
+	 * that case.
+	 */
+	if (ret == WT_ROLLBACK || ret == WT_CACHE_FULL)
+		return (ret);
 	WT_RET_MSG(bloom->session,
 	    ret == WT_NOTFOUND ? WT_ERROR : ret,
 	    "Failed lookup in bloom filter");
diff --git a/src/third_party/wiredtiger/src/btree/bt_curnext.c b/src/third_party/wiredtiger/src/btree/bt_curnext.c
index 02cceab3123..3a031b49db5 100644
--- a/src/third_party/wiredtiger/src/btree/bt_curnext.c
+++ b/src/third_party/wiredtiger/src/btree/bt_curnext.c
@@ -429,7 +429,8 @@ __cursor_key_order_check_row(
 	WT_ERR(__wt_scr_alloc(session, 512, &b));
 
 	WT_PANIC_ERR(session, EINVAL,
-	    "WT_CURSOR.%s out-of-order returns: returned key %s then key %s",
+	    "WT_CURSOR.%s out-of-order returns: returned key %.1024s then "
+	    "key %.1024s",
 	    next ? "next" : "prev",
 	    __wt_buf_set_printable_format(session,
 	    cbt->lastkey->data, cbt->lastkey->size, btree->key_format, a),
diff --git a/src/third_party/wiredtiger/src/btree/bt_debug.c b/src/third_party/wiredtiger/src/btree/bt_debug.c
index 566157abd61..16e25c1fe25 100644
--- a/src/third_party/wiredtiger/src/btree/bt_debug.c
+++ b/src/third_party/wiredtiger/src/btree/bt_debug.c
@@ -805,11 +805,13 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
 	WT_PAGE_INDEX *pindex;
 	WT_PAGE_MODIFY *mod;
 	WT_SESSION_IMPL *session;
+	uint64_t split_gen;
 	uint32_t entries;
 
 	session = ds->session;
 	page = ref->page;
 	mod = page->modify;
+	split_gen = 0;
 
 	WT_RET(ds->f(ds, "%p", (void *)ref));
 
@@ -818,6 +820,7 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
 		WT_RET(ds->f(ds, " recno %" PRIu64, ref->ref_recno));
 		WT_INTL_INDEX_GET(session, page, pindex);
 		entries = pindex->entries;
+		split_gen = page->pg_intl_split_gen;
 		break;
 	case WT_PAGE_COL_FIX:
 		WT_RET(ds->f(ds, " recno %" PRIu64, ref->ref_recno));
@@ -830,6 +833,7 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
 	case WT_PAGE_ROW_INT:
 		WT_INTL_INDEX_GET(session, page, pindex);
 		entries = pindex->entries;
+		split_gen = page->pg_intl_split_gen;
 		break;
 	case WT_PAGE_ROW_LEAF:
 		entries = page->entries;
@@ -845,8 +849,6 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
 	WT_RET(ds->f(ds, ", entries %" PRIu32, entries));
 	WT_RET(ds->f(ds,
 	    ", %s", __wt_page_is_modified(page) ? "dirty" : "clean"));
-	WT_RET(ds->f(ds,
-	    ", memory_size %" WT_SIZET_FMT, page->memory_footprint));
 
 	if (F_ISSET_ATOMIC(page, WT_PAGE_BUILD_KEYS))
 		WT_RET(ds->f(ds, ", keys-built"));
@@ -878,9 +880,12 @@ __debug_page_metadata(WT_DBG *ds, WT_REF *ref)
 			break;
 		WT_ILLEGAL_VALUE(session);
 		}
+	if (split_gen != 0)
+		WT_RET(ds->f(ds, ", split-gen=%" PRIu64, split_gen));
 	if (mod != NULL)
-		WT_RET(
-		    ds->f(ds, ", write generation=%" PRIu32, mod->write_gen));
+		WT_RET(ds->f(ds, ", write-gen=%" PRIu32, mod->write_gen));
+	WT_RET(ds->f(ds,
+	    ", memory-size %" WT_SIZET_FMT, page->memory_footprint));
 	WT_RET(ds->f(ds, "\n"));
 
 	return (0);
diff --git a/src/third_party/wiredtiger/src/btree/bt_random.c b/src/third_party/wiredtiger/src/btree/bt_random.c
index 17497561248..4f310b27237 100644
--- a/src/third_party/wiredtiger/src/btree/bt_random.c
+++ b/src/third_party/wiredtiger/src/btree/bt_random.c
@@ -262,7 +262,7 @@ restart:	/*
 		 * holding nothing on failure.
 		 */
 descend:	if ((ret = __wt_page_swap(
-		    session, current, descent, false, flags)) == 0) {
+		    session, current, descent, flags)) == 0) {
 			current = descent;
 			continue;
 		}
diff --git a/src/third_party/wiredtiger/src/btree/bt_read.c b/src/third_party/wiredtiger/src/btree/bt_read.c
index 9e530be4f0e..c8368624d3c 100644
--- a/src/third_party/wiredtiger/src/btree/bt_read.c
+++ b/src/third_party/wiredtiger/src/btree/bt_read.c
@@ -276,13 +276,15 @@ __las_page_instantiate(WT_SESSION_IMPL *session, WT_REF *ref)
 		 */
 		page->modify->first_dirty_txn = WT_TXN_FIRST;
 
-		if (ref->page_las->las_skew_newest &&
+		FLD_SET(page->modify->restore_state, WT_PAGE_RS_LOOKASIDE);
+
+		if (ref->page_las->skew_newest &&
 		    !S2C(session)->txn_global.has_stable_timestamp &&
-		    __wt_txn_visible_all(session, ref->page_las->las_max_txn,
-		    WT_TIMESTAMP_NULL(&ref->page_las->onpage_timestamp))) {
-			page->modify->rec_max_txn = ref->page_las->las_max_txn;
+		    __wt_txn_visible_all(session, ref->page_las->unstable_txn,
+		    WT_TIMESTAMP_NULL(&ref->page_las->unstable_timestamp))) {
+			page->modify->rec_max_txn = ref->page_las->max_txn;
 			__wt_timestamp_set(&page->modify->rec_max_timestamp,
-			    &ref->page_las->onpage_timestamp);
+			    &ref->page_las->max_timestamp);
 			__wt_page_modify_clear(session, page);
 		}
 	}
diff --git a/src/third_party/wiredtiger/src/btree/bt_split.c b/src/third_party/wiredtiger/src/btree/bt_split.c
index 62212607f18..a98de6c6c9f 100644
--- a/src/third_party/wiredtiger/src/btree/bt_split.c
+++ b/src/third_party/wiredtiger/src/btree/bt_split.c
@@ -1414,6 +1414,7 @@ __split_multi_inmem(
 	WT_DECL_ITEM(key);
 	WT_DECL_RET;
 	WT_PAGE *page;
+	WT_PAGE_MODIFY *mod;
 	WT_SAVE_UPD *supd;
 	WT_UPDATE *upd;
 	uint64_t recno;
@@ -1520,17 +1521,26 @@ __split_multi_inmem(
 	 * might be older than that. Set the first dirty transaction to an
 	 * impossibly old value so this page is never skipped in a checkpoint.
 	 */
-	page->modify->first_dirty_txn = WT_TXN_FIRST;
+	mod = page->modify;
+	mod->first_dirty_txn = WT_TXN_FIRST;
 
 	/*
 	 * If the new page is modified, save the eviction generation to avoid
 	 * repeatedly attempting eviction on the same page.
 	 */
-	page->modify->last_evict_pass_gen = orig->modify->last_evict_pass_gen;
-	page->modify->last_eviction_id = orig->modify->last_eviction_id;
-	__wt_timestamp_set(&page->modify->last_eviction_timestamp,
+	mod->last_evict_pass_gen = orig->modify->last_evict_pass_gen;
+	mod->last_eviction_id = orig->modify->last_eviction_id;
+	__wt_timestamp_set(&mod->last_eviction_timestamp,
 	    &orig->modify->last_eviction_timestamp);
-	page->modify->update_restored = 1;
+
+	/* Add the update/restore flag to any previous state. */
+	__wt_timestamp_set(&mod->last_stable_timestamp,
+	    &orig->modify->last_stable_timestamp);
+	mod->rec_max_txn = orig->modify->rec_max_txn;
+	__wt_timestamp_set(&mod->rec_max_timestamp,
+	    &orig->modify->rec_max_timestamp);
+	mod->restore_state = orig->modify->restore_state;
+	FLD_SET(mod->restore_state, WT_PAGE_RS_RESTORED);
 
 err:	/* Free any resources that may have been cached in the cursor. */
 	WT_TRET(__wt_btcur_close(&cbt, true));
@@ -1684,7 +1694,7 @@ __wt_multi_to_ref(WT_SESSION_IMPL *session,
 
 		WT_RET(__wt_calloc_one(session, &ref->page_las));
 		*ref->page_las = multi->page_las;
-		WT_ASSERT(session, ref->page_las->las_max_txn != WT_TXN_NONE);
+		WT_ASSERT(session, ref->page_las->max_txn != WT_TXN_NONE);
 		ref->state = WT_REF_LOOKASIDE;
 	}
 
diff --git a/src/third_party/wiredtiger/src/btree/bt_walk.c b/src/third_party/wiredtiger/src/btree/bt_walk.c
index d445184b7dd..a2386d907c7 100644
--- a/src/third_party/wiredtiger/src/btree/bt_walk.c
+++ b/src/third_party/wiredtiger/src/btree/bt_walk.c
@@ -176,44 +176,96 @@ __ref_ascend(WT_SESSION_IMPL *session,
 }
 
 /*
- * __ref_initial_descent_prev --
- *	Descend the tree one level, when setting up the initial cursor position
- * for a previous-cursor walk.
+ * __split_prev_race --
+ *	Check for races when descending the tree during a previous-cursor walk.
  */
 static inline bool
-__ref_initial_descent_prev(
+__split_prev_race(
     WT_SESSION_IMPL *session, WT_REF *ref, WT_PAGE_INDEX **pindexp)
 {
 	WT_PAGE_INDEX *pindex;
 
 	/*
-	 * When splitting an internal page into its parent, we move the WT_REF
-	 * structures and update the parent's page index before updating the
-	 * split page's page index, and it's not an atomic update. A thread can
-	 * read the parent page's replacement page index, then read the split
-	 * page's original index, or the parent page's original and the split
-	 * page's replacement.
+	 * Handle a cursor moving backwards through the tree or setting up at
+	 * the end of the tree. We're passed the child page into which we're
+	 * descending, and the parent page's page-index we used to find that
+	 * child page.
 	 *
-	 * This isn't a problem for a cursor setting up at the start of the tree
-	 * because we do right-hand splits on internal pages and the initial
-	 * part of the split page's namespace won't change as part of a split.
-	 * A thread reading the parent page's and split page's indexes will move
-	 * to the same slot no matter what order of indexes are read.
-	 *
-	 * Handle a cursor setting up at the end of the tree.
+	 * When splitting an internal page into its parent, we move the split
+	 * pages WT_REF structures, then update the parent's page index, then
+	 * update the split page's page index, and nothing is atomic. A thread
+	 * can read the parent page's replacement page index and then the split
+	 * page's original index, or vice-versa, and either change can cause a
+	 * cursor moving backwards through the tree to skip pages.
 	 *
-	 * We're passed a child page into which we're descending, and on which
-	 * we have a hazard pointer.
+	 * This isn't a problem for a cursor setting up at the start of the tree
+	 * or moving forward through the tree because we do right-hand splits on
+	 * internal pages and the initial part of the split page's namespace
+	 * won't change as part of a split (in other words, a thread reading the
+	 * parent page's and split page's indexes will move to the same slot no
+	 * matter what order of indexes are read.
 	 *
-	 * Acquire a page index for the child page and then confirm we haven't
-	 * raced with a parent split.
+	 * Acquire the child's page index, then confirm the parent's page index
+	 * hasn't changed, to check for reading an old version of the parent's
+	 * page index and then reading a new version of the child's page index.
 	 */
 	WT_INTL_INDEX_GET(session, ref->page, pindex);
 	if (__wt_split_descent_race(session, ref, *pindexp))
-		return (false);
+		return (true);
+
+	/*
+	 * That doesn't check if we read a new version of parent's page index
+	 * and then an old version of the child's page index. For example, if
+	 * a thread were in a newly created split page subtree, the split
+	 * completes into the parent before the thread reads it and descends
+	 * into the child (where the split hasn't yet completed).
+	 *
+	 * Imagine an internal page with 3 child pages, with the namespaces a-f,
+	 * g-h and i-j; the first child page splits. The parent starts out with
+	 * the following page-index:
+	 *
+	 *	| ... | a | g | i | ... |
+	 *
+	 * The split page starts out with the following page-index:
+	 *
+	 *	| a | b | c | d | e | f |
+	 *
+	 * The first step is to move the c-f ranges into a new subtree, so, for
+	 * example we might have two new internal pages 'c' and 'e', where the
+	 * new 'c' page references the c-d namespace and the new 'e' page
+	 * references the e-f namespace. The top of the subtree references the
+	 * parent page, but until the parent's page index is updated, threads in
+	 * the subtree won't be able to ascend out of the subtree. However, once
+	 * the parent page's page index is updated to this:
+	 *
+	 *	| ... | a | c | e | g | i | ... |
+	 *
+	 * threads in the subtree can ascend into the parent. Imagine a cursor
+	 * in the c-d part of the namespace that ascends to the parent's 'c'
+	 * slot. It would then decrement to the slot before the 'c' slot, the
+	 * 'a' slot.
+	 *
+	 * The previous-cursor movement selects the last slot in the 'a' page;
+	 * if the split page's page-index hasn't been updated yet, it selects
+	 * the 'f' slot, which is incorrect. Once the split page's page index is
+	 * updated to this:
+	 *
+	 *	| a | b |
+	 *
+	 * the previous-cursor movement will select the 'b' slot, which is
+	 * correct.
+	 *
+	 * If the last slot on the page no longer points to the current page as
+	 * its "home", the page is being split and part of its namespace moved,
+	 * restart. (We probably don't have to restart, I think we could spin
+	 * until the page-index is updated, but I'm not willing to debug that
+	 * one if I'm wrong.)
+	 */
+	if (pindex->index[pindex->entries - 1]->home != ref->page)
+		return (true);
 
 	*pindexp = pindex;
-	return (true);
+	return (false);
 }
 
 /*
@@ -229,22 +281,21 @@ __tree_walk_internal(WT_SESSION_IMPL *session,
 	WT_BTREE *btree;
 	WT_DECL_RET;
 	WT_PAGE_INDEX *pindex;
-	WT_REF *couple, *couple_orig, *ref;
+	WT_REF *couple, *ref, *ref_orig;
 	uint64_t sleep_usecs, yield_count;
 	uint32_t current_state, slot;
-	bool empty_internal, initial_descent, prev, skip;
+	bool empty_internal, prev, skip;
 
 	btree = S2BT(session);
 	pindex = NULL;
 	sleep_usecs = yield_count = 0;
-	empty_internal = initial_descent = false;
+	empty_internal = false;
 
 	/*
-	 * Tree walks are special: they look inside page structures that splits
-	 * may want to free.  Publish that the tree is active during this
-	 * window.
+	 * We're not supposed to walk trees without root pages. As this has not
+	 * always been the case, assert to debug that change.
 	 */
-	WT_ENTER_PAGE_INDEX(session);
+	WT_ASSERT(session, btree->root.page != NULL);
 
 	/* Check whether deleted pages can be skipped. */
 	if (!LF_ISSET(WT_READ_DELETED_SKIP))
@@ -284,36 +335,41 @@ __tree_walk_internal(WT_SESSION_IMPL *session,
 	 * new leaf, couple to the next page to which we're descending, it
 	 * saves a hazard-pointer swap for each cursor page movement.
 	 *
-	 * !!!
-	 * NOTE: we depend on the fact it's OK to release a page we don't hold,
-	 * that is, it's OK to release couple when couple is set to NULL.
-	 *
-	 * Take a copy of any held page and clear the return value.  Remember
-	 * the hazard pointer we're currently holding.
-	 *
-	 * Clear the returned value, it makes future error handling easier.
+	 * The hazard pointer on the original location is held until the end of
+	 * the movement, in case we have to restart the movement. Take a copy
+	 * of any held page and clear the return value (it makes future error
+	 * handling easier).
 	 */
-	couple = couple_orig = ref = *refp;
+	couple = NULL;
+	ref_orig = *refp;
 	*refp = NULL;
 
+	/*
+	 * Tree walks are special: they look inside page structures that splits
+	 * may want to free. Publish the tree is active during this window.
+	 */
+	WT_ENTER_PAGE_INDEX(session);
+
 	/* If no page is active, begin a walk from the start/end of the tree. */
-	if (ref == NULL) {
-restart:	/*
-		 * We can be here with a NULL or root WT_REF; the page release
-		 * function handles them internally, don't complicate this code
-		 * by calling them out.
-		 */
-		WT_ERR(__wt_page_release(session, couple, flags));
+	if ((ref = ref_orig) == NULL) {
+		if (0) {
+restart:		/*
+			 * Yield before retrying, and if we've yielded enough
+			 * times, start sleeping so we don't burn CPU to no
+			 * purpose.
+			 */
+			__wt_spin_backoff(&yield_count, &sleep_usecs);
 
-		/*
-		 * We're not supposed to walk trees without root pages. As this
-		 * has not always been the case, assert to debug that change.
-		 */
-		WT_ASSERT(session, btree->root.page != NULL);
+			WT_ERR(__wt_page_release(session, couple, flags));
+			couple = NULL;
+		}
 
-		couple = couple_orig = ref = &btree->root;
-		initial_descent = true;
-		goto descend;
+		if ((ref = ref_orig) == NULL) {
+			ref = &btree->root;
+			WT_INTL_INDEX_GET(session, ref->page, pindex);
+			slot = prev ? pindex->entries - 1 : 0;
+			goto descend;
+		}
 	}
 
 	/*
@@ -340,12 +396,9 @@ restart:	/*
 
 			/*
 			 * If at the root and returning internal pages, return
-			 * the root page, otherwise we're done. Regardless, no
-			 * hazard pointer is required, release the one we hold.
+			 * the root page, otherwise we're done.
 			 */
 			if (__wt_ref_is_root(ref)) {
-				WT_ERR(__wt_page_release(
-				    session, couple, flags));
 				if (!LF_ISSET(WT_READ_SKIP_INTL))
 					*refp = ref;
 				goto done;
@@ -356,7 +409,7 @@ restart:	/*
 			 * all of the child pages were deleted, mark it for
 			 * eviction.
 			 */
-			if (empty_internal && pindex->entries > 1) {
+			if (empty_internal) {
 				__wt_page_evict_soon(session, ref);
 				empty_internal = false;
 			}
@@ -367,17 +420,18 @@ restart:	/*
 			 * handle restart or not-found returns, it would require
 			 * additional complexity and is not a possible return:
 			 * we're moving to the parent of the current child page,
-			 * the parent can't have been evicted. (This is why we
-			 * don't pass "prev" to the page-swap function, we can't
-			 * handle the restart error returned if the parent page
-			 * is currently splitting.)
+			 * the parent can't have been evicted.
 			 */
 			if (!LF_ISSET(WT_READ_SKIP_INTL)) {
 				WT_ERR(__wt_page_swap(
-				    session, couple, ref, false, flags));
+				    session, couple, ref, flags));
+				couple = NULL;
 				*refp = ref;
 				goto done;
 			}
+
+			/* Encourage races. */
+			__wt_timing_stress(session, WT_TIMING_STRESS_SPLIT_8);
 		}
 
 		if (prev)
@@ -389,9 +443,9 @@ restart:	/*
 			++*walkcntp;
 
 		for (;;) {
-			/*
-			 * Move to the next slot, and set the reference hint if
-			 * it's wrong (used when we continue the walk). We don't
+descend:		/*
+			 * Get a reference, setting the reference hint if it's
+			 * wrong (used when we continue the walk). We don't
 			 * always update the hints when splitting, it's expected
 			 * for them to be incorrect in some workloads.
 			 */
@@ -452,12 +506,41 @@ restart:	/*
 					break;
 			}
 
-			ret = __wt_page_swap(session, couple, ref, prev,
+			ret = __wt_page_swap(session, couple, ref,
 			    WT_READ_NOTFOUND_OK | WT_READ_RESTART_OK | flags);
+			if (ret == 0) {
+				/* Success, so "couple" has been released. */
+				couple = NULL;
+
+				/* Return leaf pages to our caller. */
+				if (!WT_PAGE_IS_INTERNAL(ref->page)) {
+					*refp = ref;
+					goto done;
+				}
+
+				/* Set the new "couple" value. */
+				couple = ref;
+
+				/* Configure traversal of any internal page. */
+				empty_internal = true;
+				if (prev) {
+					if (__split_prev_race(
+					    session, ref, &pindex))
+						goto restart;
+					slot = pindex->entries - 1;
+				} else {
+					WT_INTL_INDEX_GET(
+					    session, ref->page, pindex);
+					slot = 0;
+				}
+				continue;
+			}
 
 			/*
-			 * Not-found is an expected return when only walking
+			 * Not-found is an expected return when walking only
 			 * in-cache pages, or if we see a deleted page.
+			 *
+			 * An expected error, so "couple" is unchanged.
 			 */
 			if (ret == WT_NOTFOUND) {
 				WT_NOT_READ(ret, 0);
@@ -466,94 +549,24 @@ restart:	/*
 
 			/*
 			 * The page we're moving to might have split, in which
-			 * case move to the last position we held.
-			 */
-			if (ret == WT_RESTART) {
-				ret = 0;
-
-				/*
-				 * Yield before retrying, and if we've yielded
-				 * enough times, start sleeping so we don't burn
-				 * CPU to no purpose.
-				 */
-				__wt_spin_backoff(
-				    &yield_count, &sleep_usecs);
-
-				/*
-				 * If a cursor is setting up at the end of the
-				 * tree, we can't use our parent page's index,
-				 * because it may have already split; restart
-				 * the walk.
-				 */
-				if (prev && initial_descent)
-					goto restart;
-
-				/*
-				 * If a new walk that never coupled from the
-				 * root to a new saved position in the tree,
-				 * restart the walk.
-				 */
-				if (couple == &btree->root)
-					goto restart;
-
-				/*
-				 * If restarting from some original position,
-				 * repeat the increment or decrement we made at
-				 * that time. Otherwise, couple is an internal
-				 * page we've acquired after moving from that
-				 * starting position and we can treat it as a
-				 * new page. This works because we never acquire
-				 * a hazard pointer on a leaf page we're not
-				 * going to return to our caller, this will quit
-				 * working if that ever changes.
-				 */
-				WT_ASSERT(session,
-				    couple == couple_orig ||
-				    WT_PAGE_IS_INTERNAL(couple->page));
-				ref = couple;
-				__ref_index_slot(session, ref, &pindex, &slot);
-				if (couple == couple_orig)
-					break;
-			}
-			WT_ERR(ret);
-			couple = ref;
-
-			/*
-			 * A new page: configure for traversal of any internal
-			 * page's children, else return the leaf page.
+			 * case restart the movement.
+			 *
+			 * An expected error, so "couple" is unchanged.
 			 */
-			if (WT_PAGE_IS_INTERNAL(ref->page)) {
-descend:			empty_internal = true;
-
-				/*
-				 * There's a split race when a cursor is setting
-				 * up at the end of the tree.
-				 */
-				if (prev && initial_descent) {
-					if (!__ref_initial_descent_prev(
-					    session, ref, &pindex))
-						goto restart;
-				} else
-					WT_INTL_INDEX_GET(
-					    session, ref->page, pindex);
-				slot = prev ? pindex->entries - 1 : 0;
-				continue;
-			}
+			if (ret == WT_RESTART)
+				goto restart;
 
-			/*
-			 * The tree-walk restart code knows we return any leaf
-			 * page we acquire (never hazard-pointer coupling on
-			 * after acquiring a leaf page), and asserts no restart
-			 * happens while holding a leaf page. This page must be
-			 * returned to our caller.
-			 */
-			*refp = ref;
-			goto done;
+			/* Unexpected error, so "couple" was released. */
+			couple = NULL;
+			goto err;
 		}
 	}
 
 done:
-err:	WT_LEAVE_PAGE_INDEX(session);
+err:
+	WT_TRET(__wt_page_release(session, couple, flags));
+	WT_TRET(__wt_page_release(session, ref_orig, flags));
+	WT_LEAVE_PAGE_INDEX(session);
 	return (ret);
 }
 
diff --git a/src/third_party/wiredtiger/src/btree/col_srch.c b/src/third_party/wiredtiger/src/btree/col_srch.c
index 8cc6630599b..123b640cdf4 100644
--- a/src/third_party/wiredtiger/src/btree/col_srch.c
+++ b/src/third_party/wiredtiger/src/btree/col_srch.c
@@ -179,6 +179,9 @@ descend:	/*
 			descent = pindex->index[base - 1];
 		}
 
+		/* Encourage races. */
+		__wt_timing_stress(session, WT_TIMING_STRESS_SPLIT_9);
+
 		/*
 		 * Swap the current page for the child page. If the page splits
 		 * while we're retrieving it, restart the search at the root.
@@ -192,7 +195,7 @@ descend:	/*
 		 * holding nothing on failure.
 		 */
 		if ((ret = __wt_page_swap(session,
-		    current, descent, false, WT_READ_RESTART_OK)) == 0) {
+		    current, descent, WT_READ_RESTART_OK)) == 0) {
 			current = descent;
 			continue;
 		}
diff --git a/src/third_party/wiredtiger/src/btree/row_srch.c b/src/third_party/wiredtiger/src/btree/row_srch.c
index 20acda8a1ab..a3f05a2700f 100644
--- a/src/third_party/wiredtiger/src/btree/row_srch.c
+++ b/src/third_party/wiredtiger/src/btree/row_srch.c
@@ -431,7 +431,10 @@ append:			if (__wt_split_descent_race(
 				goto restart;
 		}
 
-descend:	/*
+descend:	/* Encourage races. */
+		__wt_timing_stress(session, WT_TIMING_STRESS_SPLIT_9);
+
+		/*
 		 * Swap the current page for the child page. If the page splits
 		 * while we're retrieving it, restart the search at the root.
 		 * We cannot restart in the "current" page; for example, if a
@@ -444,7 +447,7 @@ descend:	/*
 		 * holding nothing on failure.
 		 */
 		if ((ret = __wt_page_swap(session,
-		    current, descent, false, WT_READ_RESTART_OK)) == 0) {
+		    current, descent, WT_READ_RESTART_OK)) == 0) {
 			current = descent;
 			continue;
 		}
diff --git a/src/third_party/wiredtiger/src/cache/cache_las.c b/src/third_party/wiredtiger/src/cache/cache_las.c
index 54bf8c78171..cd11a3793c5 100644
--- a/src/third_party/wiredtiger/src/cache/cache_las.c
+++ b/src/third_party/wiredtiger/src/cache/cache_las.c
@@ -404,43 +404,34 @@ __wt_las_page_skip_locked(WT_SESSION_IMPL *session, WT_REF *ref)
 		return (false);
 
 	/*
-	 * If page image has the newest version of data and includes data newer
-	 * than the reader's snapshot then we should read the history.
+	 * If some of the page's history overlaps with the reader's snapshot
+	 * then we have to read it.  This is only relevant if we chose versions
+	 * that were unstable when the page was written.
 	 */
-	if (ref->page_las->las_skew_newest &&
-	    WT_TXNID_LE(txn->snap_min, ref->page_las->las_max_txn))
+	if (ref->page_las->skew_newest &&
+	    WT_TXNID_LE(txn->snap_min, ref->page_las->unstable_txn))
 		return (false);
 
-	/*
-	 * If page image has the oldest version of data and some of the history
-	 * overlaps with the reader's snapshot then we should read the history.
-	 */
-	if (!ref->page_las->las_skew_newest &&
-	    WT_TXNID_LE(ref->page_las->las_min_txn, txn->snap_max))
-		return (false);
-
-	if (!F_ISSET(txn, WT_TXN_HAS_TS_READ) && ref->page_las->las_skew_newest)
-		return (true);
+	if (!F_ISSET(txn, WT_TXN_HAS_TS_READ))
+		return (ref->page_las->skew_newest);
 
 #ifdef HAVE_TIMESTAMPS
 	/*
 	 * Skip lookaside pages if reading as of a timestamp, we evicted new
 	 * versions of data and all the updates are in the past.
 	 */
-	if (F_ISSET(&session->txn, WT_TXN_HAS_TS_READ) &&
-	    ref->page_las->las_skew_newest &&
+	if (ref->page_las->skew_newest &&
 	    __wt_timestamp_cmp(
-	    &ref->page_las->onpage_timestamp, &session->txn.read_timestamp) < 0)
+	    &txn->read_timestamp, &ref->page_las->unstable_timestamp) > 0)
 		return (true);
 
 	/*
 	 * Skip lookaside pages if reading as of a timestamp, we evicted old
-	 * versions of data and all the updates are in the future.
+	 * versions of data and all the unstable updates are in the future.
 	 */
-	if (F_ISSET(&session->txn, WT_TXN_HAS_TS_READ) &&
-	    !ref->page_las->las_skew_newest &&
+	if (!ref->page_las->skew_newest &&
 	    __wt_timestamp_cmp(
-	    &ref->page_las->min_timestamp, &session->txn.read_timestamp) > 0)
+	    &txn->read_timestamp, &ref->page_las->unstable_timestamp) < 0)
 		return (true);
 #endif
 
@@ -563,8 +554,8 @@ __las_insert_block_verbose(WT_SESSION_IMPL *session, WT_MULTI *multi)
 		(void)__wt_eviction_dirty_needed(session, &pct_dirty);
 
 #ifdef HAVE_TIMESTAMPS
-		WT_RET(__wt_timestamp_to_hex_string(
-		    session, hex_timestamp, &multi->page_las.min_timestamp));
+		WT_RET(__wt_timestamp_to_hex_string(session, hex_timestamp,
+		    &multi->page_las.unstable_timestamp));
 		ts = hex_timestamp;
 #else
 		ts = "disabled";
@@ -573,14 +564,14 @@ __las_insert_block_verbose(WT_SESSION_IMPL *session, WT_MULTI *multi)
 		    WT_VERB_LOOKASIDE | WT_VERB_LOOKASIDE_ACTIVITY,
 		    "Page reconciliation triggered lookaside write "
 		    "file ID %" PRIu32 ", page ID %" PRIu64 ". "
-		    "Max txn ID %" PRIu64 ", min timestamp %s, skewed %s. "
+		    "Max txn ID %" PRIu64 ", unstable timestamp %s, %s. "
 		    "Entries now in lookaside file: %" PRId64 ", "
 		    "cache dirty: %2.3f%% , "
 		    "cache use: %2.3f%%",
 		    btree_id, multi->page_las.las_pageid,
-		    multi->page_las.las_max_txn,
+		    multi->page_las.max_txn,
 		    ts,
-		    multi->page_las.las_skew_newest ? "newest" : "oldest",
+		    multi->page_las.skew_newest ? "newest" : "not newest",
 		    WT_STAT_READ(conn->stats, cache_lookaside_entries),
 		    pct_dirty, pct_full);
 	}
@@ -724,8 +715,7 @@ __wt_las_insert_block(WT_SESSION_IMPL *session, WT_CURSOR *cursor,
 			 * table. (We check the length because row-store doesn't
 			 * write zero-length data items.)
 			 */
-			if (multi->page_las.las_skew_newest &&
-			    upd == list->onpage_upd &&
+			if (upd == list->onpage_upd &&
 			    upd->size > 0 &&
 			    (upd->type == WT_UPDATE_STANDARD ||
 			    upd->type == WT_UPDATE_MODIFY)) {
diff --git a/src/third_party/wiredtiger/src/config/config_def.c b/src/third_party/wiredtiger/src/config/config_def.c
index 7dee7a5e756..0945d768ce2 100644
--- a/src/third_party/wiredtiger/src/config/config_def.c
+++ b/src/third_party/wiredtiger/src/config/config_def.c
@@ -138,6 +138,7 @@ static const WT_CONFIG_CHECK confchk_WT_CONNECTION_reconfigure[] = {
 	{ "async", "category",
 	    NULL, NULL,
 	    confchk_wiredtiger_open_async_subconfigs, 3 },
+	{ "cache_max_wait_ms", "int", NULL, "min=0", NULL, 0 },
 	{ "cache_overhead", "int", NULL, "min=0,max=30", NULL, 0 },
 	{ "cache_size", "int", NULL, "min=1MB,max=10TB", NULL, 0 },
 	{ "checkpoint", "category",
@@ -189,7 +190,7 @@ static const WT_CONFIG_CHECK confchk_WT_CONNECTION_reconfigure[] = {
 	{ "timing_stress_for_test", "list",
 	    NULL, "choices=[\"checkpoint_slow\",\"lookaside_sweep_race\","
 	    "\"split_1\",\"split_2\",\"split_3\",\"split_4\",\"split_5\","
-	    "\"split_6\",\"split_7\"]",
+	    "\"split_6\",\"split_7\",\"split_8\",\"split_9\"]",
 	    NULL, 0 },
 	{ "verbose", "list",
 	    NULL, "choices=[\"api\",\"block\",\"checkpoint\","
@@ -806,6 +807,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open[] = {
 	{ "buffer_alignment", "int", NULL, "min=-1,max=1MB", NULL, 0 },
 	{ "builtin_extension_config", "string", NULL, NULL, NULL, 0 },
 	{ "cache_cursors", "boolean", NULL, NULL, NULL, 0 },
+	{ "cache_max_wait_ms", "int", NULL, "min=0", NULL, 0 },
 	{ "cache_overhead", "int", NULL, "min=0,max=30", NULL, 0 },
 	{ "cache_size", "int", NULL, "min=1MB,max=10TB", NULL, 0 },
 	{ "checkpoint", "category",
@@ -879,7 +881,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open[] = {
 	{ "timing_stress_for_test", "list",
 	    NULL, "choices=[\"checkpoint_slow\",\"lookaside_sweep_race\","
 	    "\"split_1\",\"split_2\",\"split_3\",\"split_4\",\"split_5\","
-	    "\"split_6\",\"split_7\"]",
+	    "\"split_6\",\"split_7\",\"split_8\",\"split_9\"]",
 	    NULL, 0 },
 	{ "transaction_sync", "category",
 	    NULL, NULL,
@@ -909,6 +911,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open_all[] = {
 	{ "buffer_alignment", "int", NULL, "min=-1,max=1MB", NULL, 0 },
 	{ "builtin_extension_config", "string", NULL, NULL, NULL, 0 },
 	{ "cache_cursors", "boolean", NULL, NULL, NULL, 0 },
+	{ "cache_max_wait_ms", "int", NULL, "min=0", NULL, 0 },
 	{ "cache_overhead", "int", NULL, "min=0,max=30", NULL, 0 },
 	{ "cache_size", "int", NULL, "min=1MB,max=10TB", NULL, 0 },
 	{ "checkpoint", "category",
@@ -982,7 +985,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open_all[] = {
 	{ "timing_stress_for_test", "list",
 	    NULL, "choices=[\"checkpoint_slow\",\"lookaside_sweep_race\","
 	    "\"split_1\",\"split_2\",\"split_3\",\"split_4\",\"split_5\","
-	    "\"split_6\",\"split_7\"]",
+	    "\"split_6\",\"split_7\",\"split_8\",\"split_9\"]",
 	    NULL, 0 },
 	{ "transaction_sync", "category",
 	    NULL, NULL,
@@ -1013,6 +1016,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open_basecfg[] = {
 	{ "buffer_alignment", "int", NULL, "min=-1,max=1MB", NULL, 0 },
 	{ "builtin_extension_config", "string", NULL, NULL, NULL, 0 },
 	{ "cache_cursors", "boolean", NULL, NULL, NULL, 0 },
+	{ "cache_max_wait_ms", "int", NULL, "min=0", NULL, 0 },
 	{ "cache_overhead", "int", NULL, "min=0,max=30", NULL, 0 },
 	{ "cache_size", "int", NULL, "min=1MB,max=10TB", NULL, 0 },
 	{ "checkpoint", "category",
@@ -1082,7 +1086,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open_basecfg[] = {
 	{ "timing_stress_for_test", "list",
 	    NULL, "choices=[\"checkpoint_slow\",\"lookaside_sweep_race\","
 	    "\"split_1\",\"split_2\",\"split_3\",\"split_4\",\"split_5\","
-	    "\"split_6\",\"split_7\"]",
+	    "\"split_6\",\"split_7\",\"split_8\",\"split_9\"]",
 	    NULL, 0 },
 	{ "transaction_sync", "category",
 	    NULL, NULL,
@@ -1111,6 +1115,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open_usercfg[] = {
 	{ "buffer_alignment", "int", NULL, "min=-1,max=1MB", NULL, 0 },
 	{ "builtin_extension_config", "string", NULL, NULL, NULL, 0 },
 	{ "cache_cursors", "boolean", NULL, NULL, NULL, 0 },
+	{ "cache_max_wait_ms", "int", NULL, "min=0", NULL, 0 },
 	{ "cache_overhead", "int", NULL, "min=0,max=30", NULL, 0 },
 	{ "cache_size", "int", NULL, "min=1MB,max=10TB", NULL, 0 },
 	{ "checkpoint", "category",
@@ -1180,7 +1185,7 @@ static const WT_CONFIG_CHECK confchk_wiredtiger_open_usercfg[] = {
 	{ "timing_stress_for_test", "list",
 	    NULL, "choices=[\"checkpoint_slow\",\"lookaside_sweep_race\","
 	    "\"split_1\",\"split_2\",\"split_3\",\"split_4\",\"split_5\","
-	    "\"split_6\",\"split_7\"]",
+	    "\"split_6\",\"split_7\",\"split_8\",\"split_9\"]",
 	    NULL, 0 },
 	{ "transaction_sync", "category",
 	    NULL, NULL,
@@ -1250,13 +1255,13 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  confchk_WT_CONNECTION_query_timestamp, 1
 	},
 	{ "WT_CONNECTION.reconfigure",
-	  "async=(enabled=false,ops_max=1024,threads=2),cache_overhead=8,"
-	  "cache_size=100MB,checkpoint=(log_size=0,wait=0),"
-	  "compatibility=(release=),error_prefix=,eviction=(threads_max=8,"
-	  "threads_min=1),eviction_checkpoint_target=5,"
-	  "eviction_dirty_target=5,eviction_dirty_trigger=20,"
-	  "eviction_target=80,eviction_trigger=95,"
-	  "file_manager=(close_handle_minimum=250,close_idle_time=30,"
+	  "async=(enabled=false,ops_max=1024,threads=2),cache_max_wait_ms=0"
+	  ",cache_overhead=8,cache_size=100MB,checkpoint=(log_size=0,"
+	  "wait=0),compatibility=(release=),error_prefix=,"
+	  "eviction=(threads_max=8,threads_min=1),"
+	  "eviction_checkpoint_target=1,eviction_dirty_target=5,"
+	  "eviction_dirty_trigger=20,eviction_target=80,eviction_trigger=95"
+	  ",file_manager=(close_handle_minimum=250,close_idle_time=30,"
 	  "close_scan_interval=10),log=(archive=true,prealloc=true,"
 	  "zero_fill=false),lsm_manager=(merge=true,worker_thread_max=4),"
 	  "lsm_merge=true,operation_tracking=(enabled=false,path=\".\"),"
@@ -1264,7 +1269,7 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "statistics=none,statistics_log=(json=false,on_close=false,"
 	  "sources=,timestamp=\"%b %d %H:%M:%S\",wait=0),"
 	  "timing_stress_for_test=,verbose=",
-	  confchk_WT_CONNECTION_reconfigure, 22
+	  confchk_WT_CONNECTION_reconfigure, 23
 	},
 	{ "WT_CONNECTION.rollback_to_stable",
 	  "",
@@ -1489,66 +1494,67 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	},
 	{ "wiredtiger_open",
 	  "async=(enabled=false,ops_max=1024,threads=2),buffer_alignment=-1"
-	  ",builtin_extension_config=,cache_cursors=true,cache_overhead=8,"
-	  "cache_size=100MB,checkpoint=(log_size=0,wait=0),"
-	  "checkpoint_sync=true,compatibility=(release=,require_max=,"
-	  "require_min=),config_base=true,create=false,direct_io=,"
-	  "encryption=(keyid=,name=,secretkey=),error_prefix=,"
-	  "eviction=(threads_max=8,threads_min=1),"
-	  "eviction_checkpoint_target=5,eviction_dirty_target=5,"
-	  "eviction_dirty_trigger=20,eviction_target=80,eviction_trigger=95"
-	  ",exclusive=false,extensions=,file_extend=,"
-	  "file_manager=(close_handle_minimum=250,close_idle_time=30,"
-	  "close_scan_interval=10),hazard_max=1000,in_memory=false,"
-	  "log=(archive=true,compressor=,enabled=false,file_max=100MB,"
-	  "path=\".\",prealloc=true,recover=on,zero_fill=false),"
-	  "lsm_manager=(merge=true,worker_thread_max=4),lsm_merge=true,"
-	  "mmap=true,multiprocess=false,operation_tracking=(enabled=false,"
-	  "path=\".\"),readonly=false,session_max=100,"
-	  "session_scratch_max=2MB,session_table_cache=true,"
-	  "shared_cache=(chunk=10MB,name=,quota=0,reserve=0,size=500MB),"
+	  ",builtin_extension_config=,cache_cursors=true,"
+	  "cache_max_wait_ms=0,cache_overhead=8,cache_size=100MB,"
+	  "checkpoint=(log_size=0,wait=0),checkpoint_sync=true,"
+	  "compatibility=(release=,require_max=,require_min=),"
+	  "config_base=true,create=false,direct_io=,encryption=(keyid=,"
+	  "name=,secretkey=),error_prefix=,eviction=(threads_max=8,"
+	  "threads_min=1),eviction_checkpoint_target=1,"
+	  "eviction_dirty_target=5,eviction_dirty_trigger=20,"
+	  "eviction_target=80,eviction_trigger=95,exclusive=false,"
+	  "extensions=,file_extend=,file_manager=(close_handle_minimum=250,"
+	  "close_idle_time=30,close_scan_interval=10),hazard_max=1000,"
+	  "in_memory=false,log=(archive=true,compressor=,enabled=false,"
+	  "file_max=100MB,path=\".\",prealloc=true,recover=on,"
+	  "zero_fill=false),lsm_manager=(merge=true,worker_thread_max=4),"
+	  "lsm_merge=true,mmap=true,multiprocess=false,"
+	  "operation_tracking=(enabled=false,path=\".\"),readonly=false,"
+	  "session_max=100,session_scratch_max=2MB,session_table_cache=true"
+	  ",shared_cache=(chunk=10MB,name=,quota=0,reserve=0,size=500MB),"
 	  "statistics=none,statistics_log=(json=false,on_close=false,"
 	  "path=\".\",sources=,timestamp=\"%b %d %H:%M:%S\",wait=0),"
 	  "timing_stress_for_test=,transaction_sync=(enabled=false,"
 	  "method=fsync),use_environment=true,use_environment_priv=false,"
 	  "verbose=,write_through=",
-	  confchk_wiredtiger_open, 45
+	  confchk_wiredtiger_open, 46
 	},
 	{ "wiredtiger_open_all",
 	  "async=(enabled=false,ops_max=1024,threads=2),buffer_alignment=-1"
-	  ",builtin_extension_config=,cache_cursors=true,cache_overhead=8,"
-	  "cache_size=100MB,checkpoint=(log_size=0,wait=0),"
-	  "checkpoint_sync=true,compatibility=(release=,require_max=,"
-	  "require_min=),config_base=true,create=false,direct_io=,"
-	  "encryption=(keyid=,name=,secretkey=),error_prefix=,"
-	  "eviction=(threads_max=8,threads_min=1),"
-	  "eviction_checkpoint_target=5,eviction_dirty_target=5,"
-	  "eviction_dirty_trigger=20,eviction_target=80,eviction_trigger=95"
-	  ",exclusive=false,extensions=,file_extend=,"
-	  "file_manager=(close_handle_minimum=250,close_idle_time=30,"
-	  "close_scan_interval=10),hazard_max=1000,in_memory=false,"
-	  "log=(archive=true,compressor=,enabled=false,file_max=100MB,"
-	  "path=\".\",prealloc=true,recover=on,zero_fill=false),"
-	  "lsm_manager=(merge=true,worker_thread_max=4),lsm_merge=true,"
-	  "mmap=true,multiprocess=false,operation_tracking=(enabled=false,"
-	  "path=\".\"),readonly=false,session_max=100,"
-	  "session_scratch_max=2MB,session_table_cache=true,"
-	  "shared_cache=(chunk=10MB,name=,quota=0,reserve=0,size=500MB),"
+	  ",builtin_extension_config=,cache_cursors=true,"
+	  "cache_max_wait_ms=0,cache_overhead=8,cache_size=100MB,"
+	  "checkpoint=(log_size=0,wait=0),checkpoint_sync=true,"
+	  "compatibility=(release=,require_max=,require_min=),"
+	  "config_base=true,create=false,direct_io=,encryption=(keyid=,"
+	  "name=,secretkey=),error_prefix=,eviction=(threads_max=8,"
+	  "threads_min=1),eviction_checkpoint_target=1,"
+	  "eviction_dirty_target=5,eviction_dirty_trigger=20,"
+	  "eviction_target=80,eviction_trigger=95,exclusive=false,"
+	  "extensions=,file_extend=,file_manager=(close_handle_minimum=250,"
+	  "close_idle_time=30,close_scan_interval=10),hazard_max=1000,"
+	  "in_memory=false,log=(archive=true,compressor=,enabled=false,"
+	  "file_max=100MB,path=\".\",prealloc=true,recover=on,"
+	  "zero_fill=false),lsm_manager=(merge=true,worker_thread_max=4),"
+	  "lsm_merge=true,mmap=true,multiprocess=false,"
+	  "operation_tracking=(enabled=false,path=\".\"),readonly=false,"
+	  "session_max=100,session_scratch_max=2MB,session_table_cache=true"
+	  ",shared_cache=(chunk=10MB,name=,quota=0,reserve=0,size=500MB),"
 	  "statistics=none,statistics_log=(json=false,on_close=false,"
 	  "path=\".\",sources=,timestamp=\"%b %d %H:%M:%S\",wait=0),"
 	  "timing_stress_for_test=,transaction_sync=(enabled=false,"
 	  "method=fsync),use_environment=true,use_environment_priv=false,"
 	  "verbose=,version=(major=0,minor=0),write_through=",
-	  confchk_wiredtiger_open_all, 46
+	  confchk_wiredtiger_open_all, 47
 	},
 	{ "wiredtiger_open_basecfg",
 	  "async=(enabled=false,ops_max=1024,threads=2),buffer_alignment=-1"
-	  ",builtin_extension_config=,cache_cursors=true,cache_overhead=8,"
-	  "cache_size=100MB,checkpoint=(log_size=0,wait=0),"
-	  "checkpoint_sync=true,compatibility=(release=,require_max=,"
-	  "require_min=),direct_io=,encryption=(keyid=,name=,secretkey=),"
-	  "error_prefix=,eviction=(threads_max=8,threads_min=1),"
-	  "eviction_checkpoint_target=5,eviction_dirty_target=5,"
+	  ",builtin_extension_config=,cache_cursors=true,"
+	  "cache_max_wait_ms=0,cache_overhead=8,cache_size=100MB,"
+	  "checkpoint=(log_size=0,wait=0),checkpoint_sync=true,"
+	  "compatibility=(release=,require_max=,require_min=),direct_io=,"
+	  "encryption=(keyid=,name=,secretkey=),error_prefix=,"
+	  "eviction=(threads_max=8,threads_min=1),"
+	  "eviction_checkpoint_target=1,eviction_dirty_target=5,"
 	  "eviction_dirty_trigger=20,eviction_target=80,eviction_trigger=95"
 	  ",extensions=,file_extend=,file_manager=(close_handle_minimum=250"
 	  ",close_idle_time=30,close_scan_interval=10),hazard_max=1000,"
@@ -1563,16 +1569,17 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "path=\".\",sources=,timestamp=\"%b %d %H:%M:%S\",wait=0),"
 	  "timing_stress_for_test=,transaction_sync=(enabled=false,"
 	  "method=fsync),verbose=,version=(major=0,minor=0),write_through=",
-	  confchk_wiredtiger_open_basecfg, 40
+	  confchk_wiredtiger_open_basecfg, 41
 	},
 	{ "wiredtiger_open_usercfg",
 	  "async=(enabled=false,ops_max=1024,threads=2),buffer_alignment=-1"
-	  ",builtin_extension_config=,cache_cursors=true,cache_overhead=8,"
-	  "cache_size=100MB,checkpoint=(log_size=0,wait=0),"
-	  "checkpoint_sync=true,compatibility=(release=,require_max=,"
-	  "require_min=),direct_io=,encryption=(keyid=,name=,secretkey=),"
-	  "error_prefix=,eviction=(threads_max=8,threads_min=1),"
-	  "eviction_checkpoint_target=5,eviction_dirty_target=5,"
+	  ",builtin_extension_config=,cache_cursors=true,"
+	  "cache_max_wait_ms=0,cache_overhead=8,cache_size=100MB,"
+	  "checkpoint=(log_size=0,wait=0),checkpoint_sync=true,"
+	  "compatibility=(release=,require_max=,require_min=),direct_io=,"
+	  "encryption=(keyid=,name=,secretkey=),error_prefix=,"
+	  "eviction=(threads_max=8,threads_min=1),"
+	  "eviction_checkpoint_target=1,eviction_dirty_target=5,"
 	  "eviction_dirty_trigger=20,eviction_target=80,eviction_trigger=95"
 	  ",extensions=,file_extend=,file_manager=(close_handle_minimum=250"
 	  ",close_idle_time=30,close_scan_interval=10),hazard_max=1000,"
@@ -1587,7 +1594,7 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "path=\".\",sources=,timestamp=\"%b %d %H:%M:%S\",wait=0),"
 	  "timing_stress_for_test=,transaction_sync=(enabled=false,"
 	  "method=fsync),verbose=,write_through=",
-	  confchk_wiredtiger_open_usercfg, 39
+	  confchk_wiredtiger_open_usercfg, 40
 	},
 	{ NULL, NULL, NULL, 0 }
 };
diff --git a/src/third_party/wiredtiger/src/conn/conn_api.c b/src/third_party/wiredtiger/src/conn/conn_api.c
index d322caac04a..c1e6e1eb6cf 100644
--- a/src/third_party/wiredtiger/src/conn/conn_api.c
+++ b/src/third_party/wiredtiger/src/conn/conn_api.c
@@ -2024,6 +2024,8 @@ __wt_timing_stress_config(WT_SESSION_IMPL *session, const char *cfg[])
 		{ "split_5",		WT_TIMING_STRESS_SPLIT_5 },
 		{ "split_6",		WT_TIMING_STRESS_SPLIT_6 },
 		{ "split_7",		WT_TIMING_STRESS_SPLIT_7 },
+		{ "split_8",		WT_TIMING_STRESS_SPLIT_8 },
+		{ "split_9",		WT_TIMING_STRESS_SPLIT_9 },
 		{ NULL, 0 }
 	};
 	WT_CONFIG_ITEM cval, sval;
diff --git a/src/third_party/wiredtiger/src/conn/conn_cache.c b/src/third_party/wiredtiger/src/conn/conn_cache.c
index 00de16e6c21..dbb602921a8 100644
--- a/src/third_party/wiredtiger/src/conn/conn_cache.c
+++ b/src/third_party/wiredtiger/src/conn/conn_cache.c
@@ -143,6 +143,10 @@ __cache_config_local(WT_SESSION_IMPL *session, bool shared, const char *cfg[])
 	conn->evict_threads_max = evict_threads_max;
 	conn->evict_threads_min = evict_threads_min;
 
+	/* Retrieve the wait time and convert from milliseconds */
+	WT_RET(__wt_config_gets(session, cfg, "cache_max_wait_ms", &cval));
+	cache->cache_max_wait_us = (uint64_t)(cval.val * WT_THOUSAND);
+
 	return (0);
 }
 
diff --git a/src/third_party/wiredtiger/src/evict/evict_lru.c b/src/third_party/wiredtiger/src/evict/evict_lru.c
index 8396612b7ca..05397843fc7 100644
--- a/src/third_party/wiredtiger/src/evict/evict_lru.c
+++ b/src/third_party/wiredtiger/src/evict/evict_lru.c
@@ -563,7 +563,7 @@ __evict_update_work(WT_SESSION_IMPL *session)
 	conn = S2C(session);
 	cache = conn->cache;
 
-	dirty_target = cache->eviction_dirty_target;
+	dirty_target = __wt_eviction_dirty_target(cache);
 	dirty_trigger = cache->eviction_dirty_trigger;
 	target = cache->eviction_target;
 	trigger = cache->eviction_trigger;
@@ -2345,7 +2345,8 @@ __wt_cache_eviction_worker(
 	WT_TRACK_OP_DECL;
 	WT_TXN_GLOBAL *txn_global;
 	WT_TXN_STATE *txn_state;
-	uint64_t initial_progress, max_progress, time_start, time_stop;
+	uint64_t elapsed, time_start, time_stop;
+	uint64_t initial_progress, max_progress;
 	bool timer;
 
 	WT_TRACK_OP_INIT(session);
@@ -2367,8 +2368,7 @@ __wt_cache_eviction_worker(
 	__wt_evict_server_wake(session);
 
 	/* Track how long application threads spend doing eviction. */
-	timer =
-	    WT_STAT_ENABLED(session) && !F_ISSET(session, WT_SESSION_INTERNAL);
+	timer = !F_ISSET(session, WT_SESSION_INTERNAL);
 	if (timer)
 		time_start = __wt_clock(session);
 
@@ -2405,22 +2405,10 @@ __wt_cache_eviction_worker(
 
 		/* See if eviction is still needed. */
 		if (!__wt_eviction_needed(session, busy, readonly, &pct_full) ||
-		    ((pct_full < 100.0 || cache->eviction_scrub_limit > 0.0) &&
-		    (cache->eviction_progress >
+		    (pct_full < 100.0 && (cache->eviction_progress >
 		    initial_progress + max_progress)))
 			break;
 
-		/*
-		 * Don't make application threads participate in scrubbing for
-		 * checkpoints.  Just throttle updates instead.
-		 */
-		if (WT_EVICT_HAS_WORKERS(session) &&
-		    cache->eviction_scrub_limit > 0.0 &&
-		    !F_ISSET(cache, WT_CACHE_EVICT_CLEAN_HARD)) {
-			__wt_yield();
-			continue;
-		}
-
 		/* Evict a page. */
 		switch (ret = __evict_page(session, false)) {
 		case 0:
@@ -2438,13 +2426,26 @@ __wt_cache_eviction_worker(
 		default:
 			goto err;
 		}
+		/* Stop if we've exceeded the time out. */
+		if (timer && cache->cache_max_wait_us != 0) {
+			time_stop = __wt_clock(session);
+			if (session->cache_wait_us +
+			    WT_CLOCKDIFF_US(time_stop, time_start) >
+			    cache->cache_max_wait_us)
+				goto err;
+		}
 	}
 
 err:	if (timer) {
 		time_stop = __wt_clock(session);
-		WT_STAT_CONN_INCRV(session,
-		    application_cache_time,
-		    WT_CLOCKDIFF_US(time_stop, time_start));
+		elapsed = WT_CLOCKDIFF_US(time_stop, time_start);
+		WT_STAT_CONN_INCRV(session, application_cache_time, elapsed);
+		session->cache_wait_us += elapsed;
+		if (cache->cache_max_wait_us != 0 &&
+		    session->cache_wait_us > cache->cache_max_wait_us) {
+			WT_TRET(WT_CACHE_FULL);
+			WT_STAT_CONN_INCR(session, cache_timed_out_ops);
+		}
 	}
 
 done:	WT_TRACK_OP_END(session);
diff --git a/src/third_party/wiredtiger/src/include/api.h b/src/third_party/wiredtiger/src/include/api.h
index ca2176fcf0e..aabb19c86aa 100644
--- a/src/third_party/wiredtiger/src/include/api.h
+++ b/src/third_party/wiredtiger/src/include/api.h
@@ -48,6 +48,9 @@
 	WT_TRACK_OP_INIT(s);						\
 	WT_SINGLE_THREAD_CHECK_START(s);				\
 	WT_ERR(WT_SESSION_CHECK_PANIC(s));				\
+	/* Reset wait time if this isn't an API re entry. */		\
+	if (__oldname == NULL)						\
+		(s)->cache_wait_us = 0;					\
 	__wt_verbose((s), WT_VERB_API, "%s", "CALL: " #h ":" #n)
 
 #define	API_CALL_NOCONF(s, h, n, dh) do {				\
diff --git a/src/third_party/wiredtiger/src/include/btmem.h b/src/third_party/wiredtiger/src/include/btmem.h
index 33e382feba2..64e84e59d36 100644
--- a/src/third_party/wiredtiger/src/include/btmem.h
+++ b/src/third_party/wiredtiger/src/include/btmem.h
@@ -234,14 +234,13 @@ struct __wt_ovfl_reuse {
  */
 struct __wt_page_lookaside {
 	uint64_t las_pageid;		/* Page ID in lookaside */
-	uint64_t las_max_txn;		/* Max transaction ID in lookaside */
-	uint64_t las_min_txn;		/* Min transaction ID in lookaside */
-	WT_DECL_TIMESTAMP(min_timestamp)/* Min timestamp in lookaside */
-					/* Max timestamp on page */
-	WT_DECL_TIMESTAMP(onpage_timestamp)
+	uint64_t max_txn;		/* Maximum transaction ID */
+	uint64_t unstable_txn;		/* First transaction ID not on page */
+	WT_DECL_TIMESTAMP(max_timestamp)/* Maximum timestamp */
+	WT_DECL_TIMESTAMP(unstable_timestamp)/* First timestamp not on page */
 	bool eviction_to_lookaside;	/* Revert to lookaside on eviction */
-	bool las_skew_newest;		/* On-page skewed to newest */
 	bool invalid;			/* History is required correct reads */
+	bool skew_newest;		/* Page image has newest versions */
 };
 
 /*
@@ -270,6 +269,9 @@ struct __wt_page_modify {
 	uint64_t rec_max_txn;
 	WT_DECL_TIMESTAMP(rec_max_timestamp)
 
+	/* Stable timestamp at last reconciliation. */
+	WT_DECL_TIMESTAMP(last_stable_timestamp)
+
 	/* The largest update transaction ID (approximate). */
 	uint64_t update_txn;
 
@@ -481,7 +483,9 @@ struct __wt_page_modify {
 #define	WT_PM_REC_REPLACE	3	/* Reconciliation: single block */
 	uint8_t rec_result;		/* Reconciliation state */
 
-	uint8_t update_restored;	/* Page created by restoring updates */
+#define	WT_PAGE_RS_LOOKASIDE	0x1
+#define	WT_PAGE_RS_RESTORED	0x2
+	uint8_t restore_state;		/* Created by restoring updates */
 };
 
 /*
diff --git a/src/third_party/wiredtiger/src/include/btree.i b/src/third_party/wiredtiger/src/include/btree.i
index 81c166eb0e4..d7edcd00d5a 100644
--- a/src/third_party/wiredtiger/src/include/btree.i
+++ b/src/third_party/wiredtiger/src/include/btree.i
@@ -1190,10 +1190,10 @@ __wt_page_las_active(WT_SESSION_IMPL *session, WT_REF *ref)
 
 	if ((page_las = ref->page_las) == NULL)
 		return (false);
-	if (page_las->invalid || !ref->page_las->las_skew_newest)
+	if (page_las->invalid || !ref->page_las->skew_newest)
 		return (true);
-	if (__wt_txn_visible_all(session, page_las->las_max_txn,
-	    WT_TIMESTAMP_NULL(&page_las->onpage_timestamp)))
+	if (__wt_txn_visible_all(session, page_las->max_txn,
+	    WT_TIMESTAMP_NULL(&page_las->max_timestamp)))
 		return (false);
 
 	return (true);
@@ -1329,6 +1329,7 @@ __wt_leaf_page_can_split(WT_SESSION_IMPL *session, WT_PAGE *page)
 static inline bool
 __wt_page_evict_retry(WT_SESSION_IMPL *session, WT_PAGE *page)
 {
+	WT_DECL_TIMESTAMP(pinned_ts)
 	WT_PAGE_MODIFY *mod;
 	WT_TXN_GLOBAL *txn_global;
 
@@ -1338,7 +1339,8 @@ __wt_page_evict_retry(WT_SESSION_IMPL *session, WT_PAGE *page)
 	 * If the page hasn't been through one round of update/restore, give it
 	 * a try.
 	 */
-	if ((mod = page->modify) == NULL || !mod->update_restored)
+	if ((mod = page->modify) == NULL ||
+	    !FLD_ISSET(mod->restore_state, WT_PAGE_RS_RESTORED))
 		return (true);
 
 	/*
@@ -1356,17 +1358,12 @@ __wt_page_evict_retry(WT_SESSION_IMPL *session, WT_PAGE *page)
 		return (true);
 
 #ifdef HAVE_TIMESTAMPS
-	{
-	bool same_timestamp;
-
-	same_timestamp = false;
-	if (!__wt_timestamp_iszero(&mod->last_eviction_timestamp))
-		WT_WITH_TIMESTAMP_READLOCK(session, &txn_global->rwlock,
-		    same_timestamp = __wt_timestamp_cmp(
+	if (!__wt_timestamp_iszero(&mod->last_eviction_timestamp)) {
+		__wt_txn_pinned_timestamp(session, &pinned_ts);
+		if (__wt_timestamp_cmp(
 		    &mod->last_eviction_timestamp,
-		    &txn_global->pinned_timestamp) == 0);
-	if (!same_timestamp)
-		return (true);
+		    &txn_global->pinned_timestamp) != 0)
+			return (true);
 	}
 #endif
 
@@ -1605,6 +1602,8 @@ __wt_split_descent_race(
 	 * update. A thread can read the parent page's original page index and
 	 * then read the split page's replacement index.
 	 *
+	 * For example, imagine a search descending the tree.
+	 *
 	 * Because internal page splits work by truncating the original page to
 	 * the initial part of the original page, the result of this race is we
 	 * will have a search key that points past the end of the current page.
@@ -1649,73 +1648,17 @@ __wt_split_descent_race(
 	 * work by truncating the split page, so the split page search is for
 	 * content the split page retains after the split, and we ignore this
 	 * race.
-	 */
-	WT_INTL_INDEX_GET(session, ref->home, pindex);
-	return (pindex != saved_pindex);
-}
-
-/*
- * __wt_split_prev_race --
- *	Return if we raced with an internal page split when moving backwards
- * through the tree.
- */
-static inline bool
-__wt_split_prev_race(WT_SESSION_IMPL *session, WT_REF *ref)
-{
-	WT_PAGE_INDEX *pindex;
-
-	/*
-	 * There's a split race when a cursor moving backwards through the tree
-	 * descends the tree. If we're splitting an internal page into its
-	 * parent, we move the WT_REF structures and update the parent's page
-	 * index before updating the split page's page index, and it's not an
-	 * atomic update. A thread can read the parent and split page's original
-	 * indexes during a split, or read the parent page's replacement page
-	 * index and then read the split page's original index, either of which
-	 * can lead to skipping pages.
 	 *
-	 * For example, imagine an internal page with 3 child pages, with the
-	 * namespaces a-f, g-h and i-j; the first child page splits. The parent
-	 * starts out with the following page-index:
+	 * This code is a general purpose check for a descent race and we call
+	 * it in other cases, for example, a cursor traversing backwards through
+	 * the tree.
 	 *
-	 *	| ... | a | g | i | ... |
-	 *
-	 * The split page starts out with the following page-index:
-	 *
-	 *	| a | b | c | d | e | f |
-	 *
-	 * The first step is to move the c-f ranges into a new subtree, so, for
-	 * example we might have two new internal pages 'c' and 'e', where the
-	 * new 'c' page references the c-d namespace and the new 'e' page
-	 * references the e-f namespace. The top of the subtree references the
-	 * parent page, but until the parent's page index is updated, threads in
-	 * the subtree won't be able to ascend out of the subtree. However, once
-	 * the parent page's page index is updated to this:
-	 *
-	 *	| ... | a | c | e | g | i | ... |
-	 *
-	 * threads in the subtree can ascend into the parent. Imagine a cursor
-	 * in the c-d part of the namespace that ascends to the parent's 'c'
-	 * slot. It would then decrement to the slot before the 'c' slot, the
-	 * 'a' slot.
-	 *
-	 * The previous-cursor movement selects the last slot in the 'a' page;
-	 * if the split page's page-index hasn't been updated yet, it selects
-	 * the 'f' slot, which is incorrect. Once the split page's page index is
-	 * updated to this:
-	 *
-	 *	| a | b |
-	 *
-	 * the previous-cursor movement will select the 'b' slot, which is
-	 * correct.
-	 *
-	 * This function takes an argument which is the internal page into which
-	 * we're coupling. If the last slot on the page no longer points to
-	 * the current page as its "home", the page is being split and part of
-	 * its namespace moved, we have to restart.
+	 * Presumably we acquired a page index on the child page before calling
+	 * this code, don't re-order that acquisition with this check.
 	 */
-	WT_INTL_INDEX_GET(session, ref->page, pindex);
-	return (pindex->index[pindex->entries - 1]->home != ref->page);
+	WT_BARRIER();
+	WT_INTL_INDEX_GET(session, ref->home, pindex);
+	return (pindex != saved_pindex);
 }
 
 /*
@@ -1724,8 +1667,8 @@ __wt_split_prev_race(WT_SESSION_IMPL *session, WT_REF *ref)
  * coupling up/down the tree.
  */
 static inline int
-__wt_page_swap_func(WT_SESSION_IMPL *session,
-    WT_REF *held, WT_REF *want, bool prev_race, uint32_t flags
+__wt_page_swap_func(
+    WT_SESSION_IMPL *session, WT_REF *held, WT_REF *want, uint32_t flags
 #ifdef HAVE_DIAGNOSTIC
     , const char *file, int line
 #endif
@@ -1755,18 +1698,6 @@ __wt_page_swap_func(WT_SESSION_IMPL *session,
 	    );
 
 	/*
-	 * We can race when descending into an internal page as part of moving
-	 * backwards through the tree, and we have to detect that race before
-	 * releasing the page from which we are coupling, else we can't restart
-	 * the movement.
-	 */
-	if (ret == 0 && prev_race && WT_PAGE_IS_INTERNAL(want->page) &&
-	    __wt_split_prev_race(session, want)) {
-		ret = WT_RESTART;
-		WT_TRET(__wt_page_release(session, want, flags));
-	}
-
-	/*
 	 * Expected failures: page not found or restart. Our callers list the
 	 * errors they're expecting to handle.
 	 */
diff --git a/src/third_party/wiredtiger/src/include/cache.h b/src/third_party/wiredtiger/src/include/cache.h
index 1299d3e90e3..7d07e6dfd98 100644
--- a/src/third_party/wiredtiger/src/include/cache.h
+++ b/src/third_party/wiredtiger/src/include/cache.h
@@ -120,11 +120,11 @@ struct __wt_cache {
 
 	double eviction_checkpoint_target;/* Percent to reduce dirty
 					   to during checkpoint scrubs */
-	double eviction_scrub_limit;	/* Percent of cache to trigger
-					   dirty eviction during checkpoint
-					   scrubs */
+	double eviction_scrub_target;	/* Current scrub target */
 
 	u_int overhead_pct;	        /* Cache percent adjustment */
+	uint64_t cache_max_wait_us;	/* Maximum time an operation waits for
+					 * space in cache */
 
 	/*
 	 * Eviction thread tuning information.
diff --git a/src/third_party/wiredtiger/src/include/cache.i b/src/third_party/wiredtiger/src/include/cache.i
index fc127942d02..7f12949e162 100644
--- a/src/third_party/wiredtiger/src/include/cache.i
+++ b/src/third_party/wiredtiger/src/include/cache.i
@@ -276,6 +276,22 @@ __wt_eviction_clean_needed(WT_SESSION_IMPL *session, double *pct_fullp)
 }
 
 /*
+ * __wt_eviction_dirty_target --
+ *	Return the effective dirty target (including checkpoint scrubbing).
+ */
+static inline double
+__wt_eviction_dirty_target(WT_CACHE *cache)
+{
+	double dirty_target, scrub_target;
+
+	dirty_target = cache->eviction_dirty_target;
+	scrub_target = cache->eviction_scrub_target;
+
+	return (scrub_target > 0 && scrub_target < dirty_target ?
+	    scrub_target : dirty_target);
+}
+
+/*
  * __wt_eviction_dirty_needed --
  *	Return if an application thread should do eviction due to the total
  *	volume of dirty data in cache.
@@ -284,7 +300,6 @@ static inline bool
 __wt_eviction_dirty_needed(WT_SESSION_IMPL *session, double *pct_fullp)
 {
 	WT_CACHE *cache;
-	double dirty_trigger;
 	uint64_t dirty_inuse, bytes_max;
 
 	cache = S2C(session)->cache;
@@ -299,10 +314,8 @@ __wt_eviction_dirty_needed(WT_SESSION_IMPL *session, double *pct_fullp)
 	if (pct_fullp != NULL)
 		*pct_fullp = ((100.0 * dirty_inuse) / bytes_max);
 
-	if ((dirty_trigger = cache->eviction_scrub_limit) < 1.0)
-		dirty_trigger = cache->eviction_dirty_trigger;
-
-	return (dirty_inuse > (uint64_t)(dirty_trigger * bytes_max) / 100);
+	return (dirty_inuse > (uint64_t)(
+	    cache->eviction_dirty_trigger * bytes_max) / 100);
 }
 
 /*
diff --git a/src/third_party/wiredtiger/src/include/connection.h b/src/third_party/wiredtiger/src/include/connection.h
index d0bebe8da5d..22459b0072c 100644
--- a/src/third_party/wiredtiger/src/include/connection.h
+++ b/src/third_party/wiredtiger/src/include/connection.h
@@ -458,6 +458,8 @@ struct __wt_connection_impl {
 #define	WT_TIMING_STRESS_SPLIT_5		0x040u
 #define	WT_TIMING_STRESS_SPLIT_6		0x080u
 #define	WT_TIMING_STRESS_SPLIT_7		0x100u
+#define	WT_TIMING_STRESS_SPLIT_8		0x200u
+#define	WT_TIMING_STRESS_SPLIT_9		0x400u
 /* AUTOMATIC FLAG VALUE GENERATION STOP */
 	uint64_t timing_stress_flags;
 
diff --git a/src/third_party/wiredtiger/src/include/extern.h b/src/third_party/wiredtiger/src/include/extern.h
index 7e2d4a4786d..c78c460f445 100644
--- a/src/third_party/wiredtiger/src/include/extern.h
+++ b/src/third_party/wiredtiger/src/include/extern.h
@@ -498,6 +498,7 @@ extern int __wt_lsm_work_switch(WT_SESSION_IMPL *session, WT_LSM_WORK_UNIT **ent
 extern int __wt_lsm_work_bloom(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern bool __wt_lsm_chunk_visible_all(WT_SESSION_IMPL *session, WT_LSM_CHUNK *chunk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_lsm_checkpoint_chunk(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern int __wt_lsm_work_enable_evict(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_lsm_free_chunks(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_lsm_worker_start(WT_SESSION_IMPL *session, WT_LSM_WORKER_ARGS *args) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_lsm_worker_stop(WT_SESSION_IMPL *session, WT_LSM_WORKER_ARGS *args) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
diff --git a/src/third_party/wiredtiger/src/include/lsm.h b/src/third_party/wiredtiger/src/include/lsm.h
index f515e03519a..67ef28757ef 100644
--- a/src/third_party/wiredtiger/src/include/lsm.h
+++ b/src/third_party/wiredtiger/src/include/lsm.h
@@ -107,7 +107,8 @@ struct __wt_lsm_chunk {
 	uint32_t id;			/* ID used to generate URIs */
 	uint32_t generation;		/* Merge generation */
 	uint32_t refcnt;		/* Number of worker thread references */
-	uint32_t bloom_busy;		/* Number of worker thread references */
+	uint32_t bloom_busy;		/* Currently creating bloom filter */
+	uint32_t evict_enabled;		/* Eviction allowed on the chunk */
 
 	int8_t empty;			/* 1/0: checkpoint missing */
 	int8_t evicted;			/* 1/0: in-memory chunk was evicted */
@@ -129,13 +130,19 @@ struct __wt_lsm_chunk {
  * is required.
  */
 /* AUTOMATIC FLAG VALUE GENERATION START */
-#define	WT_LSM_WORK_BLOOM	0x01u	/* Create a bloom filter */
-#define	WT_LSM_WORK_DROP	0x02u	/* Drop unused chunks */
-#define	WT_LSM_WORK_FLUSH	0x04u	/* Flush a chunk to disk */
-#define	WT_LSM_WORK_MERGE	0x08u	/* Look for a tree merge */
-#define	WT_LSM_WORK_SWITCH	0x10u	/* Switch to new in-memory chunk */
+#define	WT_LSM_WORK_BLOOM		0x01u	/* Create a bloom filter */
+#define	WT_LSM_WORK_DROP		0x02u	/* Drop unused chunks */
+#define	WT_LSM_WORK_ENABLE_EVICT	0x04u	/* Create a bloom filter */
+#define	WT_LSM_WORK_FLUSH		0x08u	/* Flush a chunk to disk */
+#define	WT_LSM_WORK_MERGE		0x10u	/* Look for a tree merge */
+#define	WT_LSM_WORK_SWITCH		0x20u	/* Switch the in-memory chunk */
 /* AUTOMATIC FLAG VALUE GENERATION STOP */
 
+/* Work units that are serviced by general worker threads. */
+#define	WT_LSM_WORK_GENERAL_OPS	 					\
+	(WT_LSM_WORK_BLOOM | WT_LSM_WORK_DROP | WT_LSM_WORK_ENABLE_EVICT |\
+	WT_LSM_WORK_FLUSH | WT_LSM_WORK_SWITCH)
+
 /*
  * WT_LSM_WORK_UNIT --
  *	A definition of maintenance that an LSM tree needs done.
diff --git a/src/third_party/wiredtiger/src/include/misc.h b/src/third_party/wiredtiger/src/include/misc.h
index 1507e2d07cc..d76560d26e6 100644
--- a/src/third_party/wiredtiger/src/include/misc.h
+++ b/src/third_party/wiredtiger/src/include/misc.h
@@ -294,16 +294,15 @@ typedef void wt_timestamp_t;
 	__wt_scr_alloc_func(session, size, scratchp, __func__, __LINE__)
 #define	__wt_page_in(session, ref, flags)				\
 	__wt_page_in_func(session, ref, flags, __func__, __LINE__)
-#define	__wt_page_swap(session, held, want, prev_race, flags)		\
-	__wt_page_swap_func(						\
-	    session, held, want, prev_race, flags, __func__, __LINE__)
+#define	__wt_page_swap(session, held, want, flags)			\
+	__wt_page_swap_func(session, held, want, flags, __func__, __LINE__)
 #else
 #define	__wt_scr_alloc(session, size, scratchp)				\
 	__wt_scr_alloc_func(session, size, scratchp)
 #define	__wt_page_in(session, ref, flags)				\
 	__wt_page_in_func(session, ref, flags)
-#define	__wt_page_swap(session, held, want, prev_race, flags)		\
-	__wt_page_swap_func(session, held, want, prev_race, flags)
+#define	__wt_page_swap(session, held, want, flags)			\
+	__wt_page_swap_func(session, held, want, flags)
 #endif
 
 /* Called on unexpected code path: locate the failure. */
diff --git a/src/third_party/wiredtiger/src/include/session.h b/src/third_party/wiredtiger/src/include/session.h
index e102d7f5057..cbf572f9a23 100644
--- a/src/third_party/wiredtiger/src/include/session.h
+++ b/src/third_party/wiredtiger/src/include/session.h
@@ -141,6 +141,8 @@ struct __wt_session_impl {
 	u_int   ckpt_handle_next;	/* Next empty slot */
 	size_t  ckpt_handle_allocated;	/* Bytes allocated */
 
+	uint64_t cache_wait_us; /* Wait time for cache for current operation */
+
 	/*
 	 * Operations acting on handles.
 	 *
diff --git a/src/third_party/wiredtiger/src/include/stat.h b/src/third_party/wiredtiger/src/include/stat.h
index 92f28d88e62..1693b9baa82 100644
--- a/src/third_party/wiredtiger/src/include/stat.h
+++ b/src/third_party/wiredtiger/src/include/stat.h
@@ -406,6 +406,7 @@ struct __wt_connection_stats {
 	int64_t cache_eviction_maximum_page_size;
 	int64_t cache_eviction_dirty;
 	int64_t cache_eviction_app_dirty;
+	int64_t cache_timed_out_ops;
 	int64_t cache_read_overflow;
 	int64_t cache_eviction_deepen;
 	int64_t cache_write_lookaside;
@@ -663,6 +664,7 @@ struct __wt_connection_stats {
 	int64_t txn_pinned_checkpoint_range;
 	int64_t txn_pinned_snapshot_range;
 	int64_t txn_pinned_timestamp;
+	int64_t txn_pinned_timestamp_checkpoint;
 	int64_t txn_pinned_timestamp_oldest;
 	int64_t txn_sync;
 	int64_t txn_commit;
diff --git a/src/third_party/wiredtiger/src/include/txn.h b/src/third_party/wiredtiger/src/include/txn.h
index 32234dca23e..480d31b188e 100644
--- a/src/third_party/wiredtiger/src/include/txn.h
+++ b/src/third_party/wiredtiger/src/include/txn.h
@@ -147,7 +147,7 @@ struct __wt_txn_global {
 	volatile bool	  checkpoint_running;	/* Checkpoint running */
 	volatile uint32_t checkpoint_id;	/* Checkpoint's session ID */
 	WT_TXN_STATE	  checkpoint_state;	/* Checkpoint's txn state */
-	WT_TXN           *checkpoint_txn;	/* Checkpoint's txn structure */
+	WT_DECL_TIMESTAMP(checkpoint_timestamp)	/* Checkpoint's timestamp */
 
 	volatile uint64_t metadata_pinned;	/* Oldest ID for metadata */
 
diff --git a/src/third_party/wiredtiger/src/include/txn.i b/src/third_party/wiredtiger/src/include/txn.i
index 9276ca62903..0efc32811e6 100644
--- a/src/third_party/wiredtiger/src/include/txn.i
+++ b/src/third_party/wiredtiger/src/include/txn.i
@@ -396,6 +396,60 @@ __wt_txn_oldest_id(WT_SESSION_IMPL *session)
 	return (checkpoint_pinned);
 }
 
+#ifdef HAVE_TIMESTAMPS
+/*
+ * __wt_txn_pinned_timestamp --
+ *	Get the first timestamp that has to be kept for the current tree.
+ */
+static inline void
+__wt_txn_pinned_timestamp(WT_SESSION_IMPL *session, wt_timestamp_t *pinned_tsp)
+{
+	WT_BTREE *btree;
+	WT_TXN_GLOBAL *txn_global;
+	wt_timestamp_t checkpoint_ts, pinned_ts;
+	bool include_checkpoint_txn;
+
+	btree = S2BT_SAFE(session);
+	txn_global = &S2C(session)->txn_global;
+
+	WT_WITH_TIMESTAMP_READLOCK(session, &txn_global->rwlock,
+	    __wt_timestamp_set(&pinned_ts, &txn_global->pinned_timestamp));
+	__wt_timestamp_set(pinned_tsp, &pinned_ts);
+
+	/*
+	 * Checkpoint transactions often fall behind ordinary application
+	 * threads.  Take special effort to not keep changes pinned in cache if
+	 * they are only required for the checkpoint and it has already seen
+	 * them.
+	 *
+	 * If there is no active checkpoint or this handle is up to date with
+	 * the active checkpoint then it's safe to ignore the checkpoint ID in
+	 * the visibility check.
+	 */
+	include_checkpoint_txn = btree == NULL ||
+	    (!F_ISSET(btree, WT_BTREE_LOOKASIDE) &&
+	    btree->checkpoint_gen != __wt_gen(session, WT_GEN_CHECKPOINT));
+	if (!include_checkpoint_txn)
+		return;
+
+	/*
+	 * The read of the timestamp pinned by a checkpoint needs to be
+	 * carefully ordered: if a checkpoint is starting and we have to use
+	 * the checkpoint timestamp, we take the minimum of it with the oldest
+	 * timestamp, which is what we want.
+	 */
+	WT_READ_BARRIER();
+
+	WT_WITH_TIMESTAMP_READLOCK(session, &txn_global->rwlock,
+	    __wt_timestamp_set(&checkpoint_ts,
+	    &txn_global->checkpoint_timestamp));
+
+	if (!__wt_timestamp_iszero(&checkpoint_ts) &&
+	    __wt_timestamp_cmp(&checkpoint_ts, &pinned_ts) < 0)
+		__wt_timestamp_set(pinned_tsp, &checkpoint_ts);
+}
+#endif
+
 /*
  * __txn_visible_all_id --
  *	Check if a given transaction ID is "globally visible".	This is, if
@@ -427,8 +481,7 @@ __wt_txn_visible_all(
 
 #ifdef HAVE_TIMESTAMPS
 	{
-	WT_TXN_GLOBAL *txn_global = &S2C(session)->txn_global;
-	int cmp;
+	wt_timestamp_t pinned_ts;
 
 	/* Timestamp check. */
 	if (timestamp == NULL || __wt_timestamp_iszero(timestamp))
@@ -438,20 +491,11 @@ __wt_txn_visible_all(
 	 * If no oldest timestamp has been supplied, updates have to stay in
 	 * cache until we are shutting down.
 	 */
-	if (!txn_global->has_pinned_timestamp)
+	if (!S2C(session)->txn_global.has_pinned_timestamp)
 		return (F_ISSET(S2C(session), WT_CONN_CLOSING));
 
-	WT_WITH_TIMESTAMP_READLOCK(session, &txn_global->rwlock,
-	    cmp = __wt_timestamp_cmp(timestamp, &txn_global->pinned_timestamp));
-
-	/*
-	 * We can discard updates with timestamps less than or equal to the
-	 * pinned timestamp.  This is different to the situation for
-	 * transaction IDs, because we know that updates with timestamps are
-	 * definitely committed (and in this case, that the transaction ID is
-	 * globally visible).
-	 */
-	return (cmp <= 0);
+	__wt_txn_pinned_timestamp(session, &pinned_ts);
+	return (__wt_timestamp_cmp(timestamp, &pinned_ts) <= 0);
 	}
 #else
 	WT_UNUSED(timestamp);
diff --git a/src/third_party/wiredtiger/src/include/wiredtiger.in b/src/third_party/wiredtiger/src/include/wiredtiger.in
index 159e9e2cf72..a4ba834d5ef 100644
--- a/src/third_party/wiredtiger/src/include/wiredtiger.in
+++ b/src/third_party/wiredtiger/src/include/wiredtiger.in
@@ -602,6 +602,14 @@ struct __wt_cursor {
 	 *
 	 * The key must first be set and the record must already exist.
 	 *
+	 * Note that reserve works by doing a special update operation that is
+	 * not logged and does not change the value of the record. This update
+	 * is aborted when the enclosing transaction ends regardless of whether
+	 * it commits or rolls back. Given that, reserve can only be used to
+	 * detect conflicts between transactions that execute concurrently. It
+	 * cannot detect all logical conflicts between transactions. For that,
+	 * some update to the record must be committed.
+	 *
 	 * @snippet ex_all.c Reserve a record
 	 *
 	 * On success, the cursor ends positioned at the specified record; to
@@ -1639,6 +1647,12 @@ struct __wt_session {
 	 * the WT_CURSOR::next (WT_CURSOR::prev) method will iterate from the
 	 * beginning (end) of the table.
 	 *
+	 * When a range truncate is in progress, and another transaction inserts
+	 * a key into that range, the behavior is not well defined - a conflict
+	 * may be detected or both transactions may be permitted to commit. If
+	 * they do commit, and if there is a crash and recovery runs, the result
+	 * may be different than what was in cache before the crash.
+	 *
 	 * @param session the session handle
 	 * @param name the URI of the table or file to truncate
 	 * @param start optional cursor marking the first record discarded;
@@ -2128,6 +2142,10 @@ struct __wt_connection {
 	 * thread uses a session from the configured session_max., an integer
 	 * between 1 and 20; default \c 2.}
 	 * @config{ ),,}
+	 * @config{cache_max_wait_ms, the maximum number of milliseconds an
+	 * application thread will wait for space to be available in cache
+	 * before giving up.  Default will wait forever., an integer greater
+	 * than or equal to 0; default \c 0.}
 	 * @config{cache_overhead, assume the heap allocator overhead is the
 	 * specified percentage\, and adjust the cache usage by that amount (for
 	 * example\, if there is 10GB of data in cache\, a percentage of 10
@@ -2179,7 +2197,7 @@ struct __wt_connection {
 	 * is a percentage of the cache size if the value is within the range of
 	 * 0 to 100 or an absolute size when greater than 100. The value is not
 	 * allowed to exceed the \c cache_size.  Ignored if set to zero or \c
-	 * in_memory is \c true., an integer between 0 and 10TB; default \c 5.}
+	 * in_memory is \c true., an integer between 0 and 10TB; default \c 1.}
 	 * @config{eviction_dirty_target, perform eviction in worker threads
 	 * when the cache contains at least this much dirty content.  It is a
 	 * percentage of the cache size if the value is within the range of 1 to
@@ -2708,6 +2726,10 @@ struct __wt_connection {
  * default value for any sessions created\, and can be overridden in configuring
  * \c cache_cursors in WT_CONNECTION.open_session., a boolean flag; default \c
  * true.}
+ * @config{cache_max_wait_ms, the maximum number of milliseconds an application
+ * thread will wait for space to be available in cache before giving up.
+ * Default will wait forever., an integer greater than or equal to 0; default \c
+ * 0.}
  * @config{cache_overhead, assume the heap allocator overhead is the specified
  * percentage\, and adjust the cache usage by that amount (for example\, if
  * there is 10GB of data in cache\, a percentage of 10 means WiredTiger treats
@@ -2808,7 +2830,7 @@ struct __wt_connection {
  * percentage of the cache size if the value is within the range of 0 to 100 or
  * an absolute size when greater than 100. The value is not allowed to exceed
  * the \c cache_size.  Ignored if set to zero or \c in_memory is \c true., an
- * integer between 0 and 10TB; default \c 5.}
+ * integer between 0 and 10TB; default \c 1.}
  * @config{eviction_dirty_target, perform eviction in worker threads when the
  * cache contains at least this much dirty content.  It is a percentage of the
  * cache size if the value is within the range of 1 to 100 or an absolute size
@@ -5103,596 +5125,600 @@ extern int wiredtiger_extension_terminate(WT_CONNECTION *connection);
 #define	WT_STAT_CONN_CACHE_EVICTION_DIRTY		1091
 /*! cache: modified pages evicted by application threads */
 #define	WT_STAT_CONN_CACHE_EVICTION_APP_DIRTY		1092
+/*! cache: operations timed out waiting for space in cache */
+#define	WT_STAT_CONN_CACHE_TIMED_OUT_OPS		1093
 /*! cache: overflow pages read into cache */
-#define	WT_STAT_CONN_CACHE_READ_OVERFLOW		1093
+#define	WT_STAT_CONN_CACHE_READ_OVERFLOW		1094
 /*! cache: page split during eviction deepened the tree */
-#define	WT_STAT_CONN_CACHE_EVICTION_DEEPEN		1094
+#define	WT_STAT_CONN_CACHE_EVICTION_DEEPEN		1095
 /*! cache: page written requiring lookaside records */
-#define	WT_STAT_CONN_CACHE_WRITE_LOOKASIDE		1095
+#define	WT_STAT_CONN_CACHE_WRITE_LOOKASIDE		1096
 /*! cache: pages currently held in the cache */
-#define	WT_STAT_CONN_CACHE_PAGES_INUSE			1096
+#define	WT_STAT_CONN_CACHE_PAGES_INUSE			1097
 /*! cache: pages evicted because they exceeded the in-memory maximum count */
-#define	WT_STAT_CONN_CACHE_EVICTION_FORCE		1097
+#define	WT_STAT_CONN_CACHE_EVICTION_FORCE		1098
 /*!
  * cache: pages evicted because they exceeded the in-memory maximum time
  * (usecs)
  */
-#define	WT_STAT_CONN_CACHE_EVICTION_FORCE_TIME		1098
+#define	WT_STAT_CONN_CACHE_EVICTION_FORCE_TIME		1099
 /*! cache: pages evicted because they had chains of deleted items count */
-#define	WT_STAT_CONN_CACHE_EVICTION_FORCE_DELETE	1099
+#define	WT_STAT_CONN_CACHE_EVICTION_FORCE_DELETE	1100
 /*!
  * cache: pages evicted because they had chains of deleted items time
  * (usecs)
  */
-#define	WT_STAT_CONN_CACHE_EVICTION_FORCE_DELETE_TIME	1100
+#define	WT_STAT_CONN_CACHE_EVICTION_FORCE_DELETE_TIME	1101
 /*! cache: pages evicted by application threads */
-#define	WT_STAT_CONN_CACHE_EVICTION_APP			1101
+#define	WT_STAT_CONN_CACHE_EVICTION_APP			1102
 /*! cache: pages queued for eviction */
-#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_QUEUED	1102
+#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_QUEUED	1103
 /*! cache: pages queued for urgent eviction */
-#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_QUEUED_URGENT	1103
+#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_QUEUED_URGENT	1104
 /*! cache: pages queued for urgent eviction during walk */
-#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_QUEUED_OLDEST	1104
+#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_QUEUED_OLDEST	1105
 /*! cache: pages read into cache */
-#define	WT_STAT_CONN_CACHE_READ				1105
+#define	WT_STAT_CONN_CACHE_READ				1106
 /*! cache: pages read into cache after truncate */
-#define	WT_STAT_CONN_CACHE_READ_DELETED			1106
+#define	WT_STAT_CONN_CACHE_READ_DELETED			1107
 /*! cache: pages read into cache after truncate in prepare state */
-#define	WT_STAT_CONN_CACHE_READ_DELETED_PREPARED	1107
+#define	WT_STAT_CONN_CACHE_READ_DELETED_PREPARED	1108
 /*! cache: pages read into cache requiring lookaside entries */
-#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE		1108
+#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE		1109
 /*! cache: pages read into cache requiring lookaside for checkpoint */
-#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_CHECKPOINT	1109
+#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_CHECKPOINT	1110
 /*! cache: pages read into cache skipping older lookaside entries */
-#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_SKIPPED	1110
+#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_SKIPPED	1111
 /*!
  * cache: pages read into cache with skipped lookaside entries needed
  * later
  */
-#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_DELAY		1111
+#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_DELAY		1112
 /*!
  * cache: pages read into cache with skipped lookaside entries needed
  * later by checkpoint
  */
-#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_DELAY_CHECKPOINT	1112
+#define	WT_STAT_CONN_CACHE_READ_LOOKASIDE_DELAY_CHECKPOINT	1113
 /*! cache: pages requested from the cache */
-#define	WT_STAT_CONN_CACHE_PAGES_REQUESTED		1113
+#define	WT_STAT_CONN_CACHE_PAGES_REQUESTED		1114
 /*! cache: pages seen by eviction walk */
-#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_SEEN		1114
+#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_SEEN		1115
 /*! cache: pages selected for eviction unable to be evicted */
-#define	WT_STAT_CONN_CACHE_EVICTION_FAIL		1115
+#define	WT_STAT_CONN_CACHE_EVICTION_FAIL		1116
 /*! cache: pages walked for eviction */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALK		1116
+#define	WT_STAT_CONN_CACHE_EVICTION_WALK		1117
 /*! cache: pages written from cache */
-#define	WT_STAT_CONN_CACHE_WRITE			1117
+#define	WT_STAT_CONN_CACHE_WRITE			1118
 /*! cache: pages written requiring in-memory restoration */
-#define	WT_STAT_CONN_CACHE_WRITE_RESTORE		1118
+#define	WT_STAT_CONN_CACHE_WRITE_RESTORE		1119
 /*! cache: percentage overhead */
-#define	WT_STAT_CONN_CACHE_OVERHEAD			1119
+#define	WT_STAT_CONN_CACHE_OVERHEAD			1120
 /*! cache: tracked bytes belonging to internal pages in the cache */
-#define	WT_STAT_CONN_CACHE_BYTES_INTERNAL		1120
+#define	WT_STAT_CONN_CACHE_BYTES_INTERNAL		1121
 /*! cache: tracked bytes belonging to leaf pages in the cache */
-#define	WT_STAT_CONN_CACHE_BYTES_LEAF			1121
+#define	WT_STAT_CONN_CACHE_BYTES_LEAF			1122
 /*! cache: tracked dirty bytes in the cache */
-#define	WT_STAT_CONN_CACHE_BYTES_DIRTY			1122
+#define	WT_STAT_CONN_CACHE_BYTES_DIRTY			1123
 /*! cache: tracked dirty pages in the cache */
-#define	WT_STAT_CONN_CACHE_PAGES_DIRTY			1123
+#define	WT_STAT_CONN_CACHE_PAGES_DIRTY			1124
 /*! cache: unmodified pages evicted */
-#define	WT_STAT_CONN_CACHE_EVICTION_CLEAN		1124
+#define	WT_STAT_CONN_CACHE_EVICTION_CLEAN		1125
 /*! connection: auto adjusting condition resets */
-#define	WT_STAT_CONN_COND_AUTO_WAIT_RESET		1125
+#define	WT_STAT_CONN_COND_AUTO_WAIT_RESET		1126
 /*! connection: auto adjusting condition wait calls */
-#define	WT_STAT_CONN_COND_AUTO_WAIT			1126
+#define	WT_STAT_CONN_COND_AUTO_WAIT			1127
 /*! connection: detected system time went backwards */
-#define	WT_STAT_CONN_TIME_TRAVEL			1127
+#define	WT_STAT_CONN_TIME_TRAVEL			1128
 /*! connection: files currently open */
-#define	WT_STAT_CONN_FILE_OPEN				1128
+#define	WT_STAT_CONN_FILE_OPEN				1129
 /*! connection: memory allocations */
-#define	WT_STAT_CONN_MEMORY_ALLOCATION			1129
+#define	WT_STAT_CONN_MEMORY_ALLOCATION			1130
 /*! connection: memory frees */
-#define	WT_STAT_CONN_MEMORY_FREE			1130
+#define	WT_STAT_CONN_MEMORY_FREE			1131
 /*! connection: memory re-allocations */
-#define	WT_STAT_CONN_MEMORY_GROW			1131
+#define	WT_STAT_CONN_MEMORY_GROW			1132
 /*! connection: pthread mutex condition wait calls */
-#define	WT_STAT_CONN_COND_WAIT				1132
+#define	WT_STAT_CONN_COND_WAIT				1133
 /*! connection: pthread mutex shared lock read-lock calls */
-#define	WT_STAT_CONN_RWLOCK_READ			1133
+#define	WT_STAT_CONN_RWLOCK_READ			1134
 /*! connection: pthread mutex shared lock write-lock calls */
-#define	WT_STAT_CONN_RWLOCK_WRITE			1134
+#define	WT_STAT_CONN_RWLOCK_WRITE			1135
 /*! connection: total fsync I/Os */
-#define	WT_STAT_CONN_FSYNC_IO				1135
+#define	WT_STAT_CONN_FSYNC_IO				1136
 /*! connection: total read I/Os */
-#define	WT_STAT_CONN_READ_IO				1136
+#define	WT_STAT_CONN_READ_IO				1137
 /*! connection: total write I/Os */
-#define	WT_STAT_CONN_WRITE_IO				1137
+#define	WT_STAT_CONN_WRITE_IO				1138
 /*! cursor: cursor create calls */
-#define	WT_STAT_CONN_CURSOR_CREATE			1138
+#define	WT_STAT_CONN_CURSOR_CREATE			1139
 /*! cursor: cursor insert calls */
-#define	WT_STAT_CONN_CURSOR_INSERT			1139
+#define	WT_STAT_CONN_CURSOR_INSERT			1140
 /*! cursor: cursor modify calls */
-#define	WT_STAT_CONN_CURSOR_MODIFY			1140
+#define	WT_STAT_CONN_CURSOR_MODIFY			1141
 /*! cursor: cursor next calls */
-#define	WT_STAT_CONN_CURSOR_NEXT			1141
+#define	WT_STAT_CONN_CURSOR_NEXT			1142
 /*! cursor: cursor operation restarted */
-#define	WT_STAT_CONN_CURSOR_RESTART			1142
+#define	WT_STAT_CONN_CURSOR_RESTART			1143
 /*! cursor: cursor prev calls */
-#define	WT_STAT_CONN_CURSOR_PREV			1143
+#define	WT_STAT_CONN_CURSOR_PREV			1144
 /*! cursor: cursor remove calls */
-#define	WT_STAT_CONN_CURSOR_REMOVE			1144
+#define	WT_STAT_CONN_CURSOR_REMOVE			1145
 /*! cursor: cursor reserve calls */
-#define	WT_STAT_CONN_CURSOR_RESERVE			1145
+#define	WT_STAT_CONN_CURSOR_RESERVE			1146
 /*! cursor: cursor reset calls */
-#define	WT_STAT_CONN_CURSOR_RESET			1146
+#define	WT_STAT_CONN_CURSOR_RESET			1147
 /*! cursor: cursor search calls */
-#define	WT_STAT_CONN_CURSOR_SEARCH			1147
+#define	WT_STAT_CONN_CURSOR_SEARCH			1148
 /*! cursor: cursor search near calls */
-#define	WT_STAT_CONN_CURSOR_SEARCH_NEAR			1148
+#define	WT_STAT_CONN_CURSOR_SEARCH_NEAR			1149
 /*! cursor: cursor sweep buckets */
-#define	WT_STAT_CONN_CURSOR_SWEEP_BUCKETS		1149
+#define	WT_STAT_CONN_CURSOR_SWEEP_BUCKETS		1150
 /*! cursor: cursor sweep cursors closed */
-#define	WT_STAT_CONN_CURSOR_SWEEP_CLOSED		1150
+#define	WT_STAT_CONN_CURSOR_SWEEP_CLOSED		1151
 /*! cursor: cursor sweep cursors examined */
-#define	WT_STAT_CONN_CURSOR_SWEEP_EXAMINED		1151
+#define	WT_STAT_CONN_CURSOR_SWEEP_EXAMINED		1152
 /*! cursor: cursor sweeps */
-#define	WT_STAT_CONN_CURSOR_SWEEP			1152
+#define	WT_STAT_CONN_CURSOR_SWEEP			1153
 /*! cursor: cursor update calls */
-#define	WT_STAT_CONN_CURSOR_UPDATE			1153
+#define	WT_STAT_CONN_CURSOR_UPDATE			1154
 /*! cursor: cursors cached on close */
-#define	WT_STAT_CONN_CURSOR_CACHE			1154
+#define	WT_STAT_CONN_CURSOR_CACHE			1155
 /*! cursor: cursors reused from cache */
-#define	WT_STAT_CONN_CURSOR_REOPEN			1155
+#define	WT_STAT_CONN_CURSOR_REOPEN			1156
 /*! cursor: truncate calls */
-#define	WT_STAT_CONN_CURSOR_TRUNCATE			1156
+#define	WT_STAT_CONN_CURSOR_TRUNCATE			1157
 /*! data-handle: connection data handles currently active */
-#define	WT_STAT_CONN_DH_CONN_HANDLE_COUNT		1157
+#define	WT_STAT_CONN_DH_CONN_HANDLE_COUNT		1158
 /*! data-handle: connection sweep candidate became referenced */
-#define	WT_STAT_CONN_DH_SWEEP_REF			1158
+#define	WT_STAT_CONN_DH_SWEEP_REF			1159
 /*! data-handle: connection sweep dhandles closed */
-#define	WT_STAT_CONN_DH_SWEEP_CLOSE			1159
+#define	WT_STAT_CONN_DH_SWEEP_CLOSE			1160
 /*! data-handle: connection sweep dhandles removed from hash list */
-#define	WT_STAT_CONN_DH_SWEEP_REMOVE			1160
+#define	WT_STAT_CONN_DH_SWEEP_REMOVE			1161
 /*! data-handle: connection sweep time-of-death sets */
-#define	WT_STAT_CONN_DH_SWEEP_TOD			1161
+#define	WT_STAT_CONN_DH_SWEEP_TOD			1162
 /*! data-handle: connection sweeps */
-#define	WT_STAT_CONN_DH_SWEEPS				1162
+#define	WT_STAT_CONN_DH_SWEEPS				1163
 /*! data-handle: session dhandles swept */
-#define	WT_STAT_CONN_DH_SESSION_HANDLES			1163
+#define	WT_STAT_CONN_DH_SESSION_HANDLES			1164
 /*! data-handle: session sweep attempts */
-#define	WT_STAT_CONN_DH_SESSION_SWEEPS			1164
+#define	WT_STAT_CONN_DH_SESSION_SWEEPS			1165
 /*! lock: checkpoint lock acquisitions */
-#define	WT_STAT_CONN_LOCK_CHECKPOINT_COUNT		1165
+#define	WT_STAT_CONN_LOCK_CHECKPOINT_COUNT		1166
 /*! lock: checkpoint lock application thread wait time (usecs) */
-#define	WT_STAT_CONN_LOCK_CHECKPOINT_WAIT_APPLICATION	1166
+#define	WT_STAT_CONN_LOCK_CHECKPOINT_WAIT_APPLICATION	1167
 /*! lock: checkpoint lock internal thread wait time (usecs) */
-#define	WT_STAT_CONN_LOCK_CHECKPOINT_WAIT_INTERNAL	1167
+#define	WT_STAT_CONN_LOCK_CHECKPOINT_WAIT_INTERNAL	1168
 /*!
  * lock: commit timestamp queue lock application thread time waiting for
  * the dhandle lock (usecs)
  */
-#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_WAIT_APPLICATION	1168
+#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_WAIT_APPLICATION	1169
 /*!
  * lock: commit timestamp queue lock internal thread time waiting for the
  * dhandle lock (usecs)
  */
-#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_WAIT_INTERNAL	1169
+#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_WAIT_INTERNAL	1170
 /*! lock: commit timestamp queue read lock acquisitions */
-#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_READ_COUNT	1170
+#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_READ_COUNT	1171
 /*! lock: commit timestamp queue write lock acquisitions */
-#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_WRITE_COUNT	1171
+#define	WT_STAT_CONN_LOCK_COMMIT_TIMESTAMP_WRITE_COUNT	1172
 /*!
  * lock: dhandle lock application thread time waiting for the dhandle
  * lock (usecs)
  */
-#define	WT_STAT_CONN_LOCK_DHANDLE_WAIT_APPLICATION	1172
+#define	WT_STAT_CONN_LOCK_DHANDLE_WAIT_APPLICATION	1173
 /*!
  * lock: dhandle lock internal thread time waiting for the dhandle lock
  * (usecs)
  */
-#define	WT_STAT_CONN_LOCK_DHANDLE_WAIT_INTERNAL		1173
+#define	WT_STAT_CONN_LOCK_DHANDLE_WAIT_INTERNAL		1174
 /*! lock: dhandle read lock acquisitions */
-#define	WT_STAT_CONN_LOCK_DHANDLE_READ_COUNT		1174
+#define	WT_STAT_CONN_LOCK_DHANDLE_READ_COUNT		1175
 /*! lock: dhandle write lock acquisitions */
-#define	WT_STAT_CONN_LOCK_DHANDLE_WRITE_COUNT		1175
+#define	WT_STAT_CONN_LOCK_DHANDLE_WRITE_COUNT		1176
 /*! lock: metadata lock acquisitions */
-#define	WT_STAT_CONN_LOCK_METADATA_COUNT		1176
+#define	WT_STAT_CONN_LOCK_METADATA_COUNT		1177
 /*! lock: metadata lock application thread wait time (usecs) */
-#define	WT_STAT_CONN_LOCK_METADATA_WAIT_APPLICATION	1177
+#define	WT_STAT_CONN_LOCK_METADATA_WAIT_APPLICATION	1178
 /*! lock: metadata lock internal thread wait time (usecs) */
-#define	WT_STAT_CONN_LOCK_METADATA_WAIT_INTERNAL	1178
+#define	WT_STAT_CONN_LOCK_METADATA_WAIT_INTERNAL	1179
 /*!
  * lock: read timestamp queue lock application thread time waiting for
  * the dhandle lock (usecs)
  */
-#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_WAIT_APPLICATION	1179
+#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_WAIT_APPLICATION	1180
 /*!
  * lock: read timestamp queue lock internal thread time waiting for the
  * dhandle lock (usecs)
  */
-#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_WAIT_INTERNAL	1180
+#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_WAIT_INTERNAL	1181
 /*! lock: read timestamp queue read lock acquisitions */
-#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_READ_COUNT	1181
+#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_READ_COUNT	1182
 /*! lock: read timestamp queue write lock acquisitions */
-#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_WRITE_COUNT	1182
+#define	WT_STAT_CONN_LOCK_READ_TIMESTAMP_WRITE_COUNT	1183
 /*! lock: schema lock acquisitions */
-#define	WT_STAT_CONN_LOCK_SCHEMA_COUNT			1183
+#define	WT_STAT_CONN_LOCK_SCHEMA_COUNT			1184
 /*! lock: schema lock application thread wait time (usecs) */
-#define	WT_STAT_CONN_LOCK_SCHEMA_WAIT_APPLICATION	1184
+#define	WT_STAT_CONN_LOCK_SCHEMA_WAIT_APPLICATION	1185
 /*! lock: schema lock internal thread wait time (usecs) */
-#define	WT_STAT_CONN_LOCK_SCHEMA_WAIT_INTERNAL		1185
+#define	WT_STAT_CONN_LOCK_SCHEMA_WAIT_INTERNAL		1186
 /*!
  * lock: table lock application thread time waiting for the table lock
  * (usecs)
  */
-#define	WT_STAT_CONN_LOCK_TABLE_WAIT_APPLICATION	1186
+#define	WT_STAT_CONN_LOCK_TABLE_WAIT_APPLICATION	1187
 /*!
  * lock: table lock internal thread time waiting for the table lock
  * (usecs)
  */
-#define	WT_STAT_CONN_LOCK_TABLE_WAIT_INTERNAL		1187
+#define	WT_STAT_CONN_LOCK_TABLE_WAIT_INTERNAL		1188
 /*! lock: table read lock acquisitions */
-#define	WT_STAT_CONN_LOCK_TABLE_READ_COUNT		1188
+#define	WT_STAT_CONN_LOCK_TABLE_READ_COUNT		1189
 /*! lock: table write lock acquisitions */
-#define	WT_STAT_CONN_LOCK_TABLE_WRITE_COUNT		1189
+#define	WT_STAT_CONN_LOCK_TABLE_WRITE_COUNT		1190
 /*!
  * lock: txn global lock application thread time waiting for the dhandle
  * lock (usecs)
  */
-#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_WAIT_APPLICATION	1190
+#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_WAIT_APPLICATION	1191
 /*!
  * lock: txn global lock internal thread time waiting for the dhandle
  * lock (usecs)
  */
-#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_WAIT_INTERNAL	1191
+#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_WAIT_INTERNAL	1192
 /*! lock: txn global read lock acquisitions */
-#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_READ_COUNT		1192
+#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_READ_COUNT		1193
 /*! lock: txn global write lock acquisitions */
-#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_WRITE_COUNT	1193
+#define	WT_STAT_CONN_LOCK_TXN_GLOBAL_WRITE_COUNT	1194
 /*! log: busy returns attempting to switch slots */
-#define	WT_STAT_CONN_LOG_SLOT_SWITCH_BUSY		1194
+#define	WT_STAT_CONN_LOG_SLOT_SWITCH_BUSY		1195
 /*! log: force archive time sleeping (usecs) */
-#define	WT_STAT_CONN_LOG_FORCE_ARCHIVE_SLEEP		1195
+#define	WT_STAT_CONN_LOG_FORCE_ARCHIVE_SLEEP		1196
 /*! log: log bytes of payload data */
-#define	WT_STAT_CONN_LOG_BYTES_PAYLOAD			1196
+#define	WT_STAT_CONN_LOG_BYTES_PAYLOAD			1197
 /*! log: log bytes written */
-#define	WT_STAT_CONN_LOG_BYTES_WRITTEN			1197
+#define	WT_STAT_CONN_LOG_BYTES_WRITTEN			1198
 /*! log: log files manually zero-filled */
-#define	WT_STAT_CONN_LOG_ZERO_FILLS			1198
+#define	WT_STAT_CONN_LOG_ZERO_FILLS			1199
 /*! log: log flush operations */
-#define	WT_STAT_CONN_LOG_FLUSH				1199
+#define	WT_STAT_CONN_LOG_FLUSH				1200
 /*! log: log force write operations */
-#define	WT_STAT_CONN_LOG_FORCE_WRITE			1200
+#define	WT_STAT_CONN_LOG_FORCE_WRITE			1201
 /*! log: log force write operations skipped */
-#define	WT_STAT_CONN_LOG_FORCE_WRITE_SKIP		1201
+#define	WT_STAT_CONN_LOG_FORCE_WRITE_SKIP		1202
 /*! log: log records compressed */
-#define	WT_STAT_CONN_LOG_COMPRESS_WRITES		1202
+#define	WT_STAT_CONN_LOG_COMPRESS_WRITES		1203
 /*! log: log records not compressed */
-#define	WT_STAT_CONN_LOG_COMPRESS_WRITE_FAILS		1203
+#define	WT_STAT_CONN_LOG_COMPRESS_WRITE_FAILS		1204
 /*! log: log records too small to compress */
-#define	WT_STAT_CONN_LOG_COMPRESS_SMALL			1204
+#define	WT_STAT_CONN_LOG_COMPRESS_SMALL			1205
 /*! log: log release advances write LSN */
-#define	WT_STAT_CONN_LOG_RELEASE_WRITE_LSN		1205
+#define	WT_STAT_CONN_LOG_RELEASE_WRITE_LSN		1206
 /*! log: log scan operations */
-#define	WT_STAT_CONN_LOG_SCANS				1206
+#define	WT_STAT_CONN_LOG_SCANS				1207
 /*! log: log scan records requiring two reads */
-#define	WT_STAT_CONN_LOG_SCAN_REREADS			1207
+#define	WT_STAT_CONN_LOG_SCAN_REREADS			1208
 /*! log: log server thread advances write LSN */
-#define	WT_STAT_CONN_LOG_WRITE_LSN			1208
+#define	WT_STAT_CONN_LOG_WRITE_LSN			1209
 /*! log: log server thread write LSN walk skipped */
-#define	WT_STAT_CONN_LOG_WRITE_LSN_SKIP			1209
+#define	WT_STAT_CONN_LOG_WRITE_LSN_SKIP			1210
 /*! log: log sync operations */
-#define	WT_STAT_CONN_LOG_SYNC				1210
+#define	WT_STAT_CONN_LOG_SYNC				1211
 /*! log: log sync time duration (usecs) */
-#define	WT_STAT_CONN_LOG_SYNC_DURATION			1211
+#define	WT_STAT_CONN_LOG_SYNC_DURATION			1212
 /*! log: log sync_dir operations */
-#define	WT_STAT_CONN_LOG_SYNC_DIR			1212
+#define	WT_STAT_CONN_LOG_SYNC_DIR			1213
 /*! log: log sync_dir time duration (usecs) */
-#define	WT_STAT_CONN_LOG_SYNC_DIR_DURATION		1213
+#define	WT_STAT_CONN_LOG_SYNC_DIR_DURATION		1214
 /*! log: log write operations */
-#define	WT_STAT_CONN_LOG_WRITES				1214
+#define	WT_STAT_CONN_LOG_WRITES				1215
 /*! log: logging bytes consolidated */
-#define	WT_STAT_CONN_LOG_SLOT_CONSOLIDATED		1215
+#define	WT_STAT_CONN_LOG_SLOT_CONSOLIDATED		1216
 /*! log: maximum log file size */
-#define	WT_STAT_CONN_LOG_MAX_FILESIZE			1216
+#define	WT_STAT_CONN_LOG_MAX_FILESIZE			1217
 /*! log: number of pre-allocated log files to create */
-#define	WT_STAT_CONN_LOG_PREALLOC_MAX			1217
+#define	WT_STAT_CONN_LOG_PREALLOC_MAX			1218
 /*! log: pre-allocated log files not ready and missed */
-#define	WT_STAT_CONN_LOG_PREALLOC_MISSED		1218
+#define	WT_STAT_CONN_LOG_PREALLOC_MISSED		1219
 /*! log: pre-allocated log files prepared */
-#define	WT_STAT_CONN_LOG_PREALLOC_FILES			1219
+#define	WT_STAT_CONN_LOG_PREALLOC_FILES			1220
 /*! log: pre-allocated log files used */
-#define	WT_STAT_CONN_LOG_PREALLOC_USED			1220
+#define	WT_STAT_CONN_LOG_PREALLOC_USED			1221
 /*! log: records processed by log scan */
-#define	WT_STAT_CONN_LOG_SCAN_RECORDS			1221
+#define	WT_STAT_CONN_LOG_SCAN_RECORDS			1222
 /*! log: slot close lost race */
-#define	WT_STAT_CONN_LOG_SLOT_CLOSE_RACE		1222
+#define	WT_STAT_CONN_LOG_SLOT_CLOSE_RACE		1223
 /*! log: slot close unbuffered waits */
-#define	WT_STAT_CONN_LOG_SLOT_CLOSE_UNBUF		1223
+#define	WT_STAT_CONN_LOG_SLOT_CLOSE_UNBUF		1224
 /*! log: slot closures */
-#define	WT_STAT_CONN_LOG_SLOT_CLOSES			1224
+#define	WT_STAT_CONN_LOG_SLOT_CLOSES			1225
 /*! log: slot join atomic update races */
-#define	WT_STAT_CONN_LOG_SLOT_RACES			1225
+#define	WT_STAT_CONN_LOG_SLOT_RACES			1226
 /*! log: slot join calls atomic updates raced */
-#define	WT_STAT_CONN_LOG_SLOT_YIELD_RACE		1226
+#define	WT_STAT_CONN_LOG_SLOT_YIELD_RACE		1227
 /*! log: slot join calls did not yield */
-#define	WT_STAT_CONN_LOG_SLOT_IMMEDIATE			1227
+#define	WT_STAT_CONN_LOG_SLOT_IMMEDIATE			1228
 /*! log: slot join calls found active slot closed */
-#define	WT_STAT_CONN_LOG_SLOT_YIELD_CLOSE		1228
+#define	WT_STAT_CONN_LOG_SLOT_YIELD_CLOSE		1229
 /*! log: slot join calls slept */
-#define	WT_STAT_CONN_LOG_SLOT_YIELD_SLEEP		1229
+#define	WT_STAT_CONN_LOG_SLOT_YIELD_SLEEP		1230
 /*! log: slot join calls yielded */
-#define	WT_STAT_CONN_LOG_SLOT_YIELD			1230
+#define	WT_STAT_CONN_LOG_SLOT_YIELD			1231
 /*! log: slot join found active slot closed */
-#define	WT_STAT_CONN_LOG_SLOT_ACTIVE_CLOSED		1231
+#define	WT_STAT_CONN_LOG_SLOT_ACTIVE_CLOSED		1232
 /*! log: slot joins yield time (usecs) */
-#define	WT_STAT_CONN_LOG_SLOT_YIELD_DURATION		1232
+#define	WT_STAT_CONN_LOG_SLOT_YIELD_DURATION		1233
 /*! log: slot transitions unable to find free slot */
-#define	WT_STAT_CONN_LOG_SLOT_NO_FREE_SLOTS		1233
+#define	WT_STAT_CONN_LOG_SLOT_NO_FREE_SLOTS		1234
 /*! log: slot unbuffered writes */
-#define	WT_STAT_CONN_LOG_SLOT_UNBUFFERED		1234
+#define	WT_STAT_CONN_LOG_SLOT_UNBUFFERED		1235
 /*! log: total in-memory size of compressed records */
-#define	WT_STAT_CONN_LOG_COMPRESS_MEM			1235
+#define	WT_STAT_CONN_LOG_COMPRESS_MEM			1236
 /*! log: total log buffer size */
-#define	WT_STAT_CONN_LOG_BUFFER_SIZE			1236
+#define	WT_STAT_CONN_LOG_BUFFER_SIZE			1237
 /*! log: total size of compressed records */
-#define	WT_STAT_CONN_LOG_COMPRESS_LEN			1237
+#define	WT_STAT_CONN_LOG_COMPRESS_LEN			1238
 /*! log: written slots coalesced */
-#define	WT_STAT_CONN_LOG_SLOT_COALESCED			1238
+#define	WT_STAT_CONN_LOG_SLOT_COALESCED			1239
 /*! log: yields waiting for previous log file close */
-#define	WT_STAT_CONN_LOG_CLOSE_YIELDS			1239
+#define	WT_STAT_CONN_LOG_CLOSE_YIELDS			1240
 /*! perf: file system read latency histogram (bucket 1) - 10-49ms */
-#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT50	1240
+#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT50	1241
 /*! perf: file system read latency histogram (bucket 2) - 50-99ms */
-#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT100	1241
+#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT100	1242
 /*! perf: file system read latency histogram (bucket 3) - 100-249ms */
-#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT250	1242
+#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT250	1243
 /*! perf: file system read latency histogram (bucket 4) - 250-499ms */
-#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT500	1243
+#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT500	1244
 /*! perf: file system read latency histogram (bucket 5) - 500-999ms */
-#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT1000	1244
+#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_LT1000	1245
 /*! perf: file system read latency histogram (bucket 6) - 1000ms+ */
-#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_GT1000	1245
+#define	WT_STAT_CONN_PERF_HIST_FSREAD_LATENCY_GT1000	1246
 /*! perf: file system write latency histogram (bucket 1) - 10-49ms */
-#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT50	1246
+#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT50	1247
 /*! perf: file system write latency histogram (bucket 2) - 50-99ms */
-#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT100	1247
+#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT100	1248
 /*! perf: file system write latency histogram (bucket 3) - 100-249ms */
-#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT250	1248
+#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT250	1249
 /*! perf: file system write latency histogram (bucket 4) - 250-499ms */
-#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT500	1249
+#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT500	1250
 /*! perf: file system write latency histogram (bucket 5) - 500-999ms */
-#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT1000	1250
+#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_LT1000	1251
 /*! perf: file system write latency histogram (bucket 6) - 1000ms+ */
-#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_GT1000	1251
+#define	WT_STAT_CONN_PERF_HIST_FSWRITE_LATENCY_GT1000	1252
 /*! perf: operation read latency histogram (bucket 1) - 100-249us */
-#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT250	1252
+#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT250	1253
 /*! perf: operation read latency histogram (bucket 2) - 250-499us */
-#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT500	1253
+#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT500	1254
 /*! perf: operation read latency histogram (bucket 3) - 500-999us */
-#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT1000	1254
+#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT1000	1255
 /*! perf: operation read latency histogram (bucket 4) - 1000-9999us */
-#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT10000	1255
+#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_LT10000	1256
 /*! perf: operation read latency histogram (bucket 5) - 10000us+ */
-#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_GT10000	1256
+#define	WT_STAT_CONN_PERF_HIST_OPREAD_LATENCY_GT10000	1257
 /*! perf: operation write latency histogram (bucket 1) - 100-249us */
-#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT250	1257
+#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT250	1258
 /*! perf: operation write latency histogram (bucket 2) - 250-499us */
-#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT500	1258
+#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT500	1259
 /*! perf: operation write latency histogram (bucket 3) - 500-999us */
-#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT1000	1259
+#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT1000	1260
 /*! perf: operation write latency histogram (bucket 4) - 1000-9999us */
-#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT10000	1260
+#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_LT10000	1261
 /*! perf: operation write latency histogram (bucket 5) - 10000us+ */
-#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_GT10000	1261
+#define	WT_STAT_CONN_PERF_HIST_OPWRITE_LATENCY_GT10000	1262
 /*! reconciliation: fast-path pages deleted */
-#define	WT_STAT_CONN_REC_PAGE_DELETE_FAST		1262
+#define	WT_STAT_CONN_REC_PAGE_DELETE_FAST		1263
 /*! reconciliation: page reconciliation calls */
-#define	WT_STAT_CONN_REC_PAGES				1263
+#define	WT_STAT_CONN_REC_PAGES				1264
 /*! reconciliation: page reconciliation calls for eviction */
-#define	WT_STAT_CONN_REC_PAGES_EVICTION			1264
+#define	WT_STAT_CONN_REC_PAGES_EVICTION			1265
 /*! reconciliation: pages deleted */
-#define	WT_STAT_CONN_REC_PAGE_DELETE			1265
+#define	WT_STAT_CONN_REC_PAGE_DELETE			1266
 /*! reconciliation: split bytes currently awaiting free */
-#define	WT_STAT_CONN_REC_SPLIT_STASHED_BYTES		1266
+#define	WT_STAT_CONN_REC_SPLIT_STASHED_BYTES		1267
 /*! reconciliation: split objects currently awaiting free */
-#define	WT_STAT_CONN_REC_SPLIT_STASHED_OBJECTS		1267
+#define	WT_STAT_CONN_REC_SPLIT_STASHED_OBJECTS		1268
 /*! session: open cursor count */
-#define	WT_STAT_CONN_SESSION_CURSOR_OPEN		1268
+#define	WT_STAT_CONN_SESSION_CURSOR_OPEN		1269
 /*! session: open session count */
-#define	WT_STAT_CONN_SESSION_OPEN			1269
+#define	WT_STAT_CONN_SESSION_OPEN			1270
 /*! session: table alter failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_ALTER_FAIL		1270
+#define	WT_STAT_CONN_SESSION_TABLE_ALTER_FAIL		1271
 /*! session: table alter successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_ALTER_SUCCESS	1271
+#define	WT_STAT_CONN_SESSION_TABLE_ALTER_SUCCESS	1272
 /*! session: table alter unchanged and skipped */
-#define	WT_STAT_CONN_SESSION_TABLE_ALTER_SKIP		1272
+#define	WT_STAT_CONN_SESSION_TABLE_ALTER_SKIP		1273
 /*! session: table compact failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_COMPACT_FAIL		1273
+#define	WT_STAT_CONN_SESSION_TABLE_COMPACT_FAIL		1274
 /*! session: table compact successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_COMPACT_SUCCESS	1274
+#define	WT_STAT_CONN_SESSION_TABLE_COMPACT_SUCCESS	1275
 /*! session: table create failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_CREATE_FAIL		1275
+#define	WT_STAT_CONN_SESSION_TABLE_CREATE_FAIL		1276
 /*! session: table create successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_CREATE_SUCCESS	1276
+#define	WT_STAT_CONN_SESSION_TABLE_CREATE_SUCCESS	1277
 /*! session: table drop failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_DROP_FAIL		1277
+#define	WT_STAT_CONN_SESSION_TABLE_DROP_FAIL		1278
 /*! session: table drop successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_DROP_SUCCESS		1278
+#define	WT_STAT_CONN_SESSION_TABLE_DROP_SUCCESS		1279
 /*! session: table rebalance failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_REBALANCE_FAIL	1279
+#define	WT_STAT_CONN_SESSION_TABLE_REBALANCE_FAIL	1280
 /*! session: table rebalance successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_REBALANCE_SUCCESS	1280
+#define	WT_STAT_CONN_SESSION_TABLE_REBALANCE_SUCCESS	1281
 /*! session: table rename failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_RENAME_FAIL		1281
+#define	WT_STAT_CONN_SESSION_TABLE_RENAME_FAIL		1282
 /*! session: table rename successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_RENAME_SUCCESS	1282
+#define	WT_STAT_CONN_SESSION_TABLE_RENAME_SUCCESS	1283
 /*! session: table salvage failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_SALVAGE_FAIL		1283
+#define	WT_STAT_CONN_SESSION_TABLE_SALVAGE_FAIL		1284
 /*! session: table salvage successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_SALVAGE_SUCCESS	1284
+#define	WT_STAT_CONN_SESSION_TABLE_SALVAGE_SUCCESS	1285
 /*! session: table truncate failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_TRUNCATE_FAIL	1285
+#define	WT_STAT_CONN_SESSION_TABLE_TRUNCATE_FAIL	1286
 /*! session: table truncate successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_TRUNCATE_SUCCESS	1286
+#define	WT_STAT_CONN_SESSION_TABLE_TRUNCATE_SUCCESS	1287
 /*! session: table verify failed calls */
-#define	WT_STAT_CONN_SESSION_TABLE_VERIFY_FAIL		1287
+#define	WT_STAT_CONN_SESSION_TABLE_VERIFY_FAIL		1288
 /*! session: table verify successful calls */
-#define	WT_STAT_CONN_SESSION_TABLE_VERIFY_SUCCESS	1288
+#define	WT_STAT_CONN_SESSION_TABLE_VERIFY_SUCCESS	1289
 /*! thread-state: active filesystem fsync calls */
-#define	WT_STAT_CONN_THREAD_FSYNC_ACTIVE		1289
+#define	WT_STAT_CONN_THREAD_FSYNC_ACTIVE		1290
 /*! thread-state: active filesystem read calls */
-#define	WT_STAT_CONN_THREAD_READ_ACTIVE			1290
+#define	WT_STAT_CONN_THREAD_READ_ACTIVE			1291
 /*! thread-state: active filesystem write calls */
-#define	WT_STAT_CONN_THREAD_WRITE_ACTIVE		1291
+#define	WT_STAT_CONN_THREAD_WRITE_ACTIVE		1292
 /*! thread-yield: application thread time evicting (usecs) */
-#define	WT_STAT_CONN_APPLICATION_EVICT_TIME		1292
+#define	WT_STAT_CONN_APPLICATION_EVICT_TIME		1293
 /*! thread-yield: application thread time waiting for cache (usecs) */
-#define	WT_STAT_CONN_APPLICATION_CACHE_TIME		1293
+#define	WT_STAT_CONN_APPLICATION_CACHE_TIME		1294
 /*!
  * thread-yield: connection close blocked waiting for transaction state
  * stabilization
  */
-#define	WT_STAT_CONN_TXN_RELEASE_BLOCKED		1294
+#define	WT_STAT_CONN_TXN_RELEASE_BLOCKED		1295
 /*! thread-yield: connection close yielded for lsm manager shutdown */
-#define	WT_STAT_CONN_CONN_CLOSE_BLOCKED_LSM		1295
+#define	WT_STAT_CONN_CONN_CLOSE_BLOCKED_LSM		1296
 /*! thread-yield: data handle lock yielded */
-#define	WT_STAT_CONN_DHANDLE_LOCK_BLOCKED		1296
+#define	WT_STAT_CONN_DHANDLE_LOCK_BLOCKED		1297
 /*!
  * thread-yield: get reference for page index and slot time sleeping
  * (usecs)
  */
-#define	WT_STAT_CONN_PAGE_INDEX_SLOT_REF_BLOCKED	1297
+#define	WT_STAT_CONN_PAGE_INDEX_SLOT_REF_BLOCKED	1298
 /*! thread-yield: log server sync yielded for log write */
-#define	WT_STAT_CONN_LOG_SERVER_SYNC_BLOCKED		1298
+#define	WT_STAT_CONN_LOG_SERVER_SYNC_BLOCKED		1299
 /*! thread-yield: page access yielded due to prepare state change */
-#define	WT_STAT_CONN_PREPARED_TRANSITION_BLOCKED_PAGE	1299
+#define	WT_STAT_CONN_PREPARED_TRANSITION_BLOCKED_PAGE	1300
 /*! thread-yield: page acquire busy blocked */
-#define	WT_STAT_CONN_PAGE_BUSY_BLOCKED			1300
+#define	WT_STAT_CONN_PAGE_BUSY_BLOCKED			1301
 /*! thread-yield: page acquire eviction blocked */
-#define	WT_STAT_CONN_PAGE_FORCIBLE_EVICT_BLOCKED	1301
+#define	WT_STAT_CONN_PAGE_FORCIBLE_EVICT_BLOCKED	1302
 /*! thread-yield: page acquire locked blocked */
-#define	WT_STAT_CONN_PAGE_LOCKED_BLOCKED		1302
+#define	WT_STAT_CONN_PAGE_LOCKED_BLOCKED		1303
 /*! thread-yield: page acquire read blocked */
-#define	WT_STAT_CONN_PAGE_READ_BLOCKED			1303
+#define	WT_STAT_CONN_PAGE_READ_BLOCKED			1304
 /*! thread-yield: page acquire time sleeping (usecs) */
-#define	WT_STAT_CONN_PAGE_SLEEP				1304
+#define	WT_STAT_CONN_PAGE_SLEEP				1305
 /*!
  * thread-yield: page delete rollback time sleeping for state change
  * (usecs)
  */
-#define	WT_STAT_CONN_PAGE_DEL_ROLLBACK_BLOCKED		1305
+#define	WT_STAT_CONN_PAGE_DEL_ROLLBACK_BLOCKED		1306
 /*! thread-yield: page reconciliation yielded due to child modification */
-#define	WT_STAT_CONN_CHILD_MODIFY_BLOCKED_PAGE		1306
+#define	WT_STAT_CONN_CHILD_MODIFY_BLOCKED_PAGE		1307
 /*! transaction: commit timestamp queue insert to empty */
-#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_EMPTY		1307
+#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_EMPTY		1308
 /*! transaction: commit timestamp queue inserts to tail */
-#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_TAIL		1308
+#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_TAIL		1309
 /*! transaction: commit timestamp queue inserts total */
-#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_INSERTS		1309
+#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_INSERTS		1310
 /*! transaction: commit timestamp queue length */
-#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_LEN		1310
+#define	WT_STAT_CONN_TXN_COMMIT_QUEUE_LEN		1311
 /*! transaction: number of named snapshots created */
-#define	WT_STAT_CONN_TXN_SNAPSHOTS_CREATED		1311
+#define	WT_STAT_CONN_TXN_SNAPSHOTS_CREATED		1312
 /*! transaction: number of named snapshots dropped */
-#define	WT_STAT_CONN_TXN_SNAPSHOTS_DROPPED		1312
+#define	WT_STAT_CONN_TXN_SNAPSHOTS_DROPPED		1313
 /*! transaction: prepared transactions */
-#define	WT_STAT_CONN_TXN_PREPARE			1313
+#define	WT_STAT_CONN_TXN_PREPARE			1314
 /*! transaction: prepared transactions committed */
-#define	WT_STAT_CONN_TXN_PREPARE_COMMIT			1314
+#define	WT_STAT_CONN_TXN_PREPARE_COMMIT			1315
 /*! transaction: prepared transactions currently active */
-#define	WT_STAT_CONN_TXN_PREPARE_ACTIVE			1315
+#define	WT_STAT_CONN_TXN_PREPARE_ACTIVE			1316
 /*! transaction: prepared transactions rolled back */
-#define	WT_STAT_CONN_TXN_PREPARE_ROLLBACK		1316
+#define	WT_STAT_CONN_TXN_PREPARE_ROLLBACK		1317
 /*! transaction: query timestamp calls */
-#define	WT_STAT_CONN_TXN_QUERY_TS			1317
+#define	WT_STAT_CONN_TXN_QUERY_TS			1318
 /*! transaction: read timestamp queue insert to empty */
-#define	WT_STAT_CONN_TXN_READ_QUEUE_EMPTY		1318
+#define	WT_STAT_CONN_TXN_READ_QUEUE_EMPTY		1319
 /*! transaction: read timestamp queue inserts to head */
-#define	WT_STAT_CONN_TXN_READ_QUEUE_HEAD		1319
+#define	WT_STAT_CONN_TXN_READ_QUEUE_HEAD		1320
 /*! transaction: read timestamp queue inserts total */
-#define	WT_STAT_CONN_TXN_READ_QUEUE_INSERTS		1320
+#define	WT_STAT_CONN_TXN_READ_QUEUE_INSERTS		1321
 /*! transaction: read timestamp queue length */
-#define	WT_STAT_CONN_TXN_READ_QUEUE_LEN			1321
+#define	WT_STAT_CONN_TXN_READ_QUEUE_LEN			1322
 /*! transaction: rollback to stable calls */
-#define	WT_STAT_CONN_TXN_ROLLBACK_TO_STABLE		1322
+#define	WT_STAT_CONN_TXN_ROLLBACK_TO_STABLE		1323
 /*! transaction: rollback to stable updates aborted */
-#define	WT_STAT_CONN_TXN_ROLLBACK_UPD_ABORTED		1323
+#define	WT_STAT_CONN_TXN_ROLLBACK_UPD_ABORTED		1324
 /*! transaction: rollback to stable updates removed from lookaside */
-#define	WT_STAT_CONN_TXN_ROLLBACK_LAS_REMOVED		1324
+#define	WT_STAT_CONN_TXN_ROLLBACK_LAS_REMOVED		1325
 /*! transaction: set timestamp calls */
-#define	WT_STAT_CONN_TXN_SET_TS				1325
+#define	WT_STAT_CONN_TXN_SET_TS				1326
 /*! transaction: set timestamp commit calls */
-#define	WT_STAT_CONN_TXN_SET_TS_COMMIT			1326
+#define	WT_STAT_CONN_TXN_SET_TS_COMMIT			1327
 /*! transaction: set timestamp commit updates */
-#define	WT_STAT_CONN_TXN_SET_TS_COMMIT_UPD		1327
+#define	WT_STAT_CONN_TXN_SET_TS_COMMIT_UPD		1328
 /*! transaction: set timestamp oldest calls */
-#define	WT_STAT_CONN_TXN_SET_TS_OLDEST			1328
+#define	WT_STAT_CONN_TXN_SET_TS_OLDEST			1329
 /*! transaction: set timestamp oldest updates */
-#define	WT_STAT_CONN_TXN_SET_TS_OLDEST_UPD		1329
+#define	WT_STAT_CONN_TXN_SET_TS_OLDEST_UPD		1330
 /*! transaction: set timestamp stable calls */
-#define	WT_STAT_CONN_TXN_SET_TS_STABLE			1330
+#define	WT_STAT_CONN_TXN_SET_TS_STABLE			1331
 /*! transaction: set timestamp stable updates */
-#define	WT_STAT_CONN_TXN_SET_TS_STABLE_UPD		1331
+#define	WT_STAT_CONN_TXN_SET_TS_STABLE_UPD		1332
 /*! transaction: transaction begins */
-#define	WT_STAT_CONN_TXN_BEGIN				1332
+#define	WT_STAT_CONN_TXN_BEGIN				1333
 /*! transaction: transaction checkpoint currently running */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1333
+#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1334
 /*! transaction: transaction checkpoint generation */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1334
+#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1335
 /*! transaction: transaction checkpoint max time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1335
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1336
 /*! transaction: transaction checkpoint min time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1336
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1337
 /*! transaction: transaction checkpoint most recent time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1337
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1338
 /*! transaction: transaction checkpoint scrub dirty target */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1338
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1339
 /*! transaction: transaction checkpoint scrub time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1339
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1340
 /*! transaction: transaction checkpoint total time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1340
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1341
 /*! transaction: transaction checkpoints */
-#define	WT_STAT_CONN_TXN_CHECKPOINT			1341
+#define	WT_STAT_CONN_TXN_CHECKPOINT			1342
 /*!
  * transaction: transaction checkpoints skipped because database was
  * clean
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SKIPPED		1342
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SKIPPED		1343
 /*! transaction: transaction failures due to cache overflow */
-#define	WT_STAT_CONN_TXN_FAIL_CACHE			1343
+#define	WT_STAT_CONN_TXN_FAIL_CACHE			1344
 /*!
  * transaction: transaction fsync calls for checkpoint after allocating
  * the transaction ID
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1344
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1345
 /*!
  * transaction: transaction fsync duration for checkpoint after
  * allocating the transaction ID (usecs)
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1345
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1346
 /*! transaction: transaction range of IDs currently pinned */
-#define	WT_STAT_CONN_TXN_PINNED_RANGE			1346
+#define	WT_STAT_CONN_TXN_PINNED_RANGE			1347
 /*! transaction: transaction range of IDs currently pinned by a checkpoint */
-#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1347
+#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1348
 /*!
  * transaction: transaction range of IDs currently pinned by named
  * snapshots
  */
-#define	WT_STAT_CONN_TXN_PINNED_SNAPSHOT_RANGE		1348
+#define	WT_STAT_CONN_TXN_PINNED_SNAPSHOT_RANGE		1349
 /*! transaction: transaction range of timestamps currently pinned */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP		1349
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP		1350
+/*! transaction: transaction range of timestamps pinned by a checkpoint */
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_CHECKPOINT	1351
 /*!
  * transaction: transaction range of timestamps pinned by the oldest
  * timestamp
  */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_OLDEST	1350
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_OLDEST	1352
 /*! transaction: transaction sync calls */
-#define	WT_STAT_CONN_TXN_SYNC				1351
+#define	WT_STAT_CONN_TXN_SYNC				1353
 /*! transaction: transactions committed */
-#define	WT_STAT_CONN_TXN_COMMIT				1352
+#define	WT_STAT_CONN_TXN_COMMIT				1354
 /*! transaction: transactions rolled back */
-#define	WT_STAT_CONN_TXN_ROLLBACK			1353
+#define	WT_STAT_CONN_TXN_ROLLBACK			1355
 /*! transaction: update conflicts */
-#define	WT_STAT_CONN_TXN_UPDATE_CONFLICT		1354
+#define	WT_STAT_CONN_TXN_UPDATE_CONFLICT		1356
 
 /*!
  * @}
diff --git a/src/third_party/wiredtiger/src/lsm/lsm_cursor.c b/src/third_party/wiredtiger/src/lsm/lsm_cursor.c
index 4d9f6f92832..13d7d857a04 100644
--- a/src/third_party/wiredtiger/src/lsm/lsm_cursor.c
+++ b/src/third_party/wiredtiger/src/lsm/lsm_cursor.c
@@ -265,6 +265,12 @@ open:		WT_WITH_SCHEMA_LOCK(session,
 	}
 
 	if (!F_ISSET(clsm, WT_CLSM_ACTIVE)) {
+		/*
+		 * Opening this LSM cursor has opened a number of btree
+		 * cursors, ensure other code doesn't think this is the first
+		 * cursor in a session.
+		 */
+		++session->ncursors;
 		WT_RET(__cursor_enter(session));
 		F_SET(clsm, WT_CLSM_ACTIVE);
 	}
@@ -284,6 +290,7 @@ __clsm_leave(WT_CURSOR_LSM *clsm)
 	session = (WT_SESSION_IMPL *)clsm->iface.session;
 
 	if (F_ISSET(clsm, WT_CLSM_ACTIVE)) {
+		--session->ncursors;
 		__cursor_leave(session);
 		F_CLR(clsm, WT_CLSM_ACTIVE);
 	}
@@ -365,12 +372,17 @@ __clsm_deleted_decode(WT_CURSOR_LSM *clsm, WT_ITEM *value)
  *	Close any btree cursors that are not needed.
  */
 static int
-__clsm_close_cursors(WT_CURSOR_LSM *clsm, u_int start, u_int end)
+__clsm_close_cursors(
+    WT_SESSION_IMPL *session, WT_CURSOR_LSM *clsm, u_int start, u_int end)
 {
 	WT_BLOOM *bloom;
 	WT_CURSOR *c;
 	u_int i;
 
+	__wt_verbose(session, WT_VERB_LSM,
+	    "LSM closing cursor session(%p):clsm(%p), start: %u, end: %u",
+	    (void *)session, (void *)clsm, start, end);
+
 	if (clsm->chunks == NULL || clsm->nchunks == 0)
 		return (0);
 
@@ -609,7 +621,7 @@ retry:	if (F_ISSET(clsm, WT_CLSM_MERGE)) {
 			saved_gen = lsm_tree->dsk_gen;
 			locked = false;
 			__wt_lsm_tree_readunlock(session, lsm_tree);
-			WT_ERR(__clsm_close_cursors(
+			WT_ERR(__clsm_close_cursors(session,
 			    clsm, close_range_start, close_range_end));
 			__wt_lsm_tree_readlock(session, lsm_tree);
 			locked = true;
@@ -626,6 +638,10 @@ retry:	if (F_ISSET(clsm, WT_CLSM_MERGE)) {
 	clsm->nchunks = nchunks;
 
 	/* Open the cursors for chunks that have changed. */
+	__wt_verbose(session, WT_VERB_LSM,
+	    "LSM opening cursor session(%p):clsm(%p)%s, chunks: %u, good: %u",
+	    (void *)session, (void *)clsm,
+	    update ? ", update" : "", nchunks, ngood);
 	for (i = ngood; i != nchunks; i++) {
 		chunk = lsm_tree->chunk[i + start_chunk];
 		/* Copy the maximum transaction ID. */
@@ -1736,7 +1752,7 @@ __wt_clsm_close(WT_CURSOR *cursor)
 	 */
 	clsm = (WT_CURSOR_LSM *)cursor;
 	CURSOR_API_CALL_PREPARE_ALLOWED(cursor, session, close, NULL);
-	WT_TRET(__clsm_close_cursors(clsm, 0, clsm->nchunks));
+	WT_TRET(__clsm_close_cursors(session, clsm, 0, clsm->nchunks));
 	__clsm_free_chunks(session, clsm);
 
 	/* In case we were somehow left positioned, clear that. */
diff --git a/src/third_party/wiredtiger/src/lsm/lsm_manager.c b/src/third_party/wiredtiger/src/lsm/lsm_manager.c
index 40ff5fc0b26..1a5c60344bc 100644
--- a/src/third_party/wiredtiger/src/lsm/lsm_manager.c
+++ b/src/third_party/wiredtiger/src/lsm/lsm_manager.c
@@ -72,11 +72,7 @@ __lsm_general_worker_start(WT_SESSION_IMPL *session)
 			worker_args->type =
 			    WT_LSM_WORK_DROP | WT_LSM_WORK_SWITCH;
 		else {
-			worker_args->type =
-			    WT_LSM_WORK_BLOOM |
-			    WT_LSM_WORK_DROP |
-			    WT_LSM_WORK_FLUSH |
-			    WT_LSM_WORK_SWITCH;
+			worker_args->type = WT_LSM_WORK_GENERAL_OPS;
 			/*
 			 * Only allow half of the threads to run merges to
 			 * avoid all all workers getting stuck in long-running
@@ -422,9 +418,10 @@ __lsm_manager_run_server(WT_SESSION_IMPL *session)
 				fillms = 10000;
 			/*
 			 * If the tree appears to not be triggering enough
-			 * LSM maintenance, help it out. Additional work units
-			 * don't hurt, and can be necessary if some work
-			 * units aren't completed for some reason.
+			 * LSM maintenance, help it out. Some types of
+			 * additional work units don't hurt, and can be
+			 * necessary if some work units aren't completed for
+			 * some reason.
 			 * If the tree hasn't been modified, and there are
 			 * more than 1 chunks - try to get the tree smaller
 			 * so queries run faster.
diff --git a/src/third_party/wiredtiger/src/lsm/lsm_work_unit.c b/src/third_party/wiredtiger/src/lsm/lsm_work_unit.c
index 6f18f4fb152..a283670eba6 100644
--- a/src/third_party/wiredtiger/src/lsm/lsm_work_unit.c
+++ b/src/third_party/wiredtiger/src/lsm/lsm_work_unit.c
@@ -313,6 +313,37 @@ __wt_lsm_chunk_visible_all(
 }
 
 /*
+ * __lsm_set_chunk_evictable --
+ *	Enable eviction in an LSM chunk.
+ */
+static int
+__lsm_set_chunk_evictable(
+    WT_SESSION_IMPL *session, WT_LSM_CHUNK *chunk, bool need_handle)
+{
+	WT_BTREE *btree;
+	WT_DECL_RET;
+
+	if (chunk->evict_enabled != 0)
+		return (0);
+
+	/* See if we win the race to enable eviction. */
+	if (__wt_atomic_cas32(&chunk->evict_enabled, 0, 1)) {
+		if (need_handle)
+			WT_RET(__wt_session_get_dhandle(
+			    session, chunk->uri, NULL, NULL, 0));
+		btree = session->dhandle->handle;
+		if (btree->evict_disabled_open) {
+			btree->evict_disabled_open = false;
+			__wt_evict_file_exclusive_off(session);
+		}
+
+		if (need_handle)
+			WT_TRET(__wt_session_release_dhandle(session));
+	}
+	return (ret);
+}
+
+/*
  * __lsm_checkpoint_chunk --
  *	Checkpoint an LSM chunk, separated out to make locking easier.
  */
@@ -340,7 +371,6 @@ int
 __wt_lsm_checkpoint_chunk(WT_SESSION_IMPL *session,
     WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk)
 {
-	WT_BTREE *btree;
 	WT_DECL_RET;
 	WT_TXN_ISOLATION saved_isolation;
 	bool flush_set, release_dhandle;
@@ -375,6 +405,14 @@ __wt_lsm_checkpoint_chunk(WT_SESSION_IMPL *session,
 	WT_RET(__wt_txn_update_oldest(
 	    session, WT_TXN_OLDEST_STRICT | WT_TXN_OLDEST_WAIT));
 	if (!__wt_lsm_chunk_visible_all(session, chunk)) {
+		/*
+		 * If there is cache pressure consider making a chunk evictable
+		 * to avoid the cache getting stuck when history is required.
+		 */
+		if (__wt_eviction_needed(session, false, false, NULL))
+			WT_ERR(__wt_lsm_manager_push_entry(
+			    session, WT_LSM_WORK_ENABLE_EVICT, 0, lsm_tree));
+
 		__wt_verbose(session, WT_VERB_LSM,
 		    "LSM worker %s: running transaction, return",
 		    chunk->uri);
@@ -446,11 +484,7 @@ __wt_lsm_checkpoint_chunk(WT_SESSION_IMPL *session,
 	 * Enable eviction on the live chunk so it doesn't block the cache.
 	 * Future reads should direct to the on-disk chunk anyway.
 	 */
-	btree = session->dhandle->handle;
-	if (btree->evict_disabled_open) {
-		btree->evict_disabled_open = false;
-		__wt_evict_file_exclusive_off(session);
-	}
+	WT_ERR(__lsm_set_chunk_evictable(session, chunk, false));
 
 	release_dhandle = false;
 	WT_ERR(__wt_session_release_dhandle(session));
@@ -481,6 +515,54 @@ err:	if (flush_set)
 }
 
 /*
+ * __wt_lsm_work_enable_evict --
+ *	LSM usually pins live chunks in memory - preferring to force them
+ *	out via a checkpoint when they are no longer required. For applications
+ *	that keep data pinned for a long time this can lead to the cache
+ *	being pinned full. This work unit detects that case, and enables
+ *	regular eviction in chunks that can be correctly evicted.
+ */
+int
+__wt_lsm_work_enable_evict(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
+{
+	WT_DECL_RET;
+	WT_LSM_CHUNK *chunk;
+	WT_LSM_WORKER_COOKIE cookie;
+	u_int i;
+
+	WT_CLEAR(cookie);
+
+	/* Only do this if there is cache pressure */
+	if (!__wt_eviction_needed(session, false, false, NULL))
+		return (0);
+
+	WT_RET(__lsm_copy_chunks(session, lsm_tree, &cookie, false));
+
+	/*
+	 * Turn on eviction in chunks that have had some chance to
+	 * checkpoint if there is cache pressure.
+	 */
+	for (i = 0; cookie.nchunks > 2 && i < cookie.nchunks - 2; i++) {
+		chunk = cookie.chunk_array[i];
+
+		/*
+		 * Skip if the chunk isn't on disk yet, or if it's still in
+		 * cache for a reason other than transaction visibility.
+		 */
+		if (!F_ISSET(chunk, WT_LSM_CHUNK_ONDISK) ||
+		    chunk->evict_enabled != 0 ||
+		    __wt_lsm_chunk_visible_all(session, chunk))
+			continue;
+
+		WT_ERR(__lsm_set_chunk_evictable(session, chunk, true));
+	}
+
+err:	__lsm_unpin_chunks(session, &cookie);
+	__wt_free(session, cookie.chunk_array);
+	return (ret);
+}
+
+/*
  * __lsm_bloom_create --
  *	Create a bloom filter for a chunk of the LSM tree that has been
  *	checkpointed but not yet been merged.
diff --git a/src/third_party/wiredtiger/src/lsm/lsm_worker.c b/src/third_party/wiredtiger/src/lsm/lsm_worker.c
index 82f72bdf355..8588737f6c3 100644
--- a/src/third_party/wiredtiger/src/lsm/lsm_worker.c
+++ b/src/third_party/wiredtiger/src/lsm/lsm_worker.c
@@ -42,7 +42,9 @@ __wt_lsm_worker_stop(WT_SESSION_IMPL *session, WT_LSM_WORKER_ARGS *args)
 
 /*
  * __lsm_worker_general_op --
- *	Execute a single bloom, drop or flush work unit.
+ *	Execute a single medium importance maintenance operation that should
+ *	not be super long running. That includes bloom creation, drop or flush
+ *	work unit types.
  */
 static int
 __lsm_worker_general_op(
@@ -55,11 +57,7 @@ __lsm_worker_general_op(
 
 	*completed = false;
 
-	/*
-	 * Return if this thread cannot process a bloom, drop or flush.
-	 */
-	if (!FLD_ISSET(cookie->type,
-	    WT_LSM_WORK_BLOOM | WT_LSM_WORK_DROP | WT_LSM_WORK_FLUSH))
+	if (!FLD_ISSET(cookie->type, WT_LSM_WORK_GENERAL_OPS))
 		return (WT_NOTFOUND);
 
 	if ((ret = __wt_lsm_manager_pop_entry(session,
@@ -88,6 +86,8 @@ __lsm_worker_general_op(
 		WT_ERR(__wt_lsm_free_chunks(session, entry->lsm_tree));
 	else if (entry->type == WT_LSM_WORK_BLOOM)
 		WT_ERR(__wt_lsm_work_bloom(session, entry->lsm_tree));
+	else if (entry->type == WT_LSM_WORK_ENABLE_EVICT)
+		WT_ERR(__wt_lsm_work_enable_evict(session, entry->lsm_tree));
 	*completed = true;
 
 err:	__wt_lsm_manager_free_work_unit(session, entry);
diff --git a/src/third_party/wiredtiger/src/reconcile/rec_write.c b/src/third_party/wiredtiger/src/reconcile/rec_write.c
index eb3b0038525..c0ce4c2d235 100644
--- a/src/third_party/wiredtiger/src/reconcile/rec_write.c
+++ b/src/third_party/wiredtiger/src/reconcile/rec_write.c
@@ -47,10 +47,11 @@ typedef struct {
 
 	/* Track the page's min/maximum transactions. */
 	uint64_t max_txn;
-	uint64_t min_txn_unstable;
 	WT_DECL_TIMESTAMP(max_timestamp)
-	WT_DECL_TIMESTAMP(max_onpage_timestamp)
-	WT_DECL_TIMESTAMP(min_saved_timestamp)
+
+	/* Lookaside boundary tracking. */
+	uint64_t unstable_txn;
+	WT_DECL_TIMESTAMP(unstable_timestamp)
 
 	u_int updates_seen;		/* Count of updates seen. */
 	u_int updates_unstable;		/* Count of updates not visible_all. */
@@ -422,14 +423,27 @@ __wt_reconcile(WT_SESSION_IMPL *session, WT_REF *ref,
 		return (EBUSY);
 	}
 
+	/* Initialize the reconciliation structure for each new run. */
+	if ((ret = __rec_init(
+	    session, ref, flags, salvage, &session->reconcile)) != 0) {
+		WT_PAGE_UNLOCK(session, page);
+		return (ret);
+	}
+	r = session->reconcile;
+
 	oldest_id = __wt_txn_oldest_id(session);
+
+	/*
+	 * During eviction, save the transaction state that causes history to
+	 * be pinned, regardless of whether reconciliation succeeds or fails.
+	 * There is usually no point retrying eviction until this state
+	 * changes.
+	 */
 	if (LF_ISSET(WT_REC_EVICT)) {
 		mod->last_eviction_id = oldest_id;
 #ifdef HAVE_TIMESTAMPS
-		WT_WITH_TIMESTAMP_READLOCK(session,
-		    &S2C(session)->txn_global.rwlock,
-		    __wt_timestamp_set(&mod->last_eviction_timestamp,
-		    &S2C(session)->txn_global.pinned_timestamp));
+		__wt_txn_pinned_timestamp(
+		    session, &mod->last_eviction_timestamp);
 #endif
 		mod->last_evict_pass_gen = S2C(session)->cache->evict_pass_gen;
 	}
@@ -444,14 +458,6 @@ __wt_reconcile(WT_SESSION_IMPL *session, WT_REF *ref,
 	mod->last_oldest_id = oldest_id;
 #endif
 
-	/* Initialize the reconciliation structure for each new run. */
-	if ((ret = __rec_init(
-	    session, ref, flags, salvage, &session->reconcile)) != 0) {
-		WT_PAGE_UNLOCK(session, page);
-		return (ret);
-	}
-	r = session->reconcile;
-
 	/* Reconcile the page. */
 	switch (page->type) {
 	case WT_PAGE_COL_FIX:
@@ -495,6 +501,17 @@ __wt_reconcile(WT_SESSION_IMPL *session, WT_REF *ref,
 	else
 		WT_TRET(__rec_write_wrapup_err(session, r, page));
 
+#ifdef HAVE_TIMESTAMPS
+	/*
+	 * If reconciliation completes successfully, save the stable timestamp.
+	 */
+	if (ret == 0 && S2C(session)->txn_global.has_stable_timestamp)
+		WT_WITH_TIMESTAMP_READLOCK(session,
+		    &S2C(session)->txn_global.rwlock,
+		    __wt_timestamp_set(&mod->last_stable_timestamp,
+		    &S2C(session)->txn_global.stable_timestamp));
+#endif
+
 	/* Release the reconciliation lock. */
 	WT_PAGE_UNLOCK(session, page);
 
@@ -681,7 +698,7 @@ __rec_write_page_status(WT_SESSION_IMPL *session, WT_RECONCILE *r)
 	} else {
 		/*
 		 * Track the page's maximum transaction ID (used to decide if
-		 * we're likely to be able to evict this page in the future).
+		 * we can evict a clean page and discard its history).
 		 */
 		mod->rec_max_txn = r->max_txn;
 		__wt_timestamp_set(&mod->rec_max_timestamp, &r->max_timestamp);
@@ -873,7 +890,6 @@ __rec_init(WT_SESSION_IMPL *session,
 	WT_PAGE *page;
 	WT_RECONCILE *r;
 	WT_TXN_GLOBAL *txn_global;
-	bool las_skew_oldest;
 
 	btree = S2BT(session);
 	page = ref->page;
@@ -928,27 +944,24 @@ __rec_init(WT_SESSION_IMPL *session,
 	 * We usually prefer to skew to newer versions, the logic being that by
 	 * the time the next checkpoint runs, it is likely that all the updates
 	 * we choose will be stable.  However, if checkpointing with a
-	 * timestamp (indicated by a stable_timestamp being set), and the
-	 * timestamp hasn't changed since the last time this page was
-	 * reconciled, skew oldest instead. If a checkpoint is already running,
-	 * the oldest version is more likely to be what it needs.
+	 * timestamp (indicated by a stable_timestamp being set), and there is
+	 * a checkpoint already running, or this page was read with lookaside
+	 * history, or the stable timestamp hasn't changed since last time this
+	 * page was successfully, skew oldest instead.
 	 */
-	if (__wt_btree_immediately_durable(session))
-		las_skew_oldest = false;
-	else {
-		WT_ORDERED_READ(las_skew_oldest,
-		    txn_global->has_stable_timestamp);
-		if (las_skew_oldest) {
-			las_skew_oldest = (ref->page_las != NULL &&
-			    !__wt_txn_visible_all(session, WT_TXN_NONE,
-			    WT_TIMESTAMP_NULL(
-			    &ref->page_las->min_timestamp))) ||
-			    btree->checkpoint_gen !=
-			    __wt_gen(session, WT_GEN_CHECKPOINT);
-		}
-	}
-	r->las_skew_newest = LF_ISSET(WT_REC_LOOKASIDE) &&
-	    LF_ISSET(WT_REC_VISIBLE_ALL) && !las_skew_oldest;
+	r->las_skew_newest =
+	    LF_ISSET(WT_REC_LOOKASIDE) && LF_ISSET(WT_REC_VISIBLE_ALL);
+#ifdef HAVE_TIMESTAMPS
+	if (r->las_skew_newest &&
+	    !__wt_btree_immediately_durable(session) &&
+	    txn_global->has_stable_timestamp &&
+	    ((btree->checkpoint_gen != __wt_gen(session, WT_GEN_CHECKPOINT) &&
+	    txn_global->stable_is_pinned) ||
+	    FLD_ISSET(page->modify->restore_state, WT_PAGE_RS_LOOKASIDE) ||
+	    __wt_timestamp_cmp(&page->modify->last_stable_timestamp,
+	    &txn_global->stable_timestamp) == 0))
+		r->las_skew_newest = false;
+#endif
 
 	/*
 	 * When operating on the lookaside table, we should never try
@@ -979,10 +992,21 @@ __rec_init(WT_SESSION_IMPL *session,
 
 	/* Track the page's min/maximum transaction */
 	r->max_txn = WT_TXN_NONE;
-	r->min_txn_unstable = WT_TXN_ABORTED;
 	__wt_timestamp_set_zero(&r->max_timestamp);
-	__wt_timestamp_set_zero(&r->max_onpage_timestamp);
-	__wt_timestamp_set_inf(&r->min_saved_timestamp);
+
+	/*
+	 * Track the first unstable transaction (when skewing newest this is
+	 * the newest update, otherwise the newest update not on the page).
+	 * This is the boundary between the on-page information and the history
+	 * stored in the lookaside table.
+	 */
+	if (r->las_skew_newest) {
+		r->unstable_txn = WT_TXN_NONE;
+		__wt_timestamp_set_zero(&r->unstable_timestamp);
+	} else {
+		r->unstable_txn = WT_TXN_ABORTED;
+		__wt_timestamp_set_inf(&r->unstable_timestamp);
+	}
 
 	/* Track if updates were used and/or uncommitted. */
 	r->updates_seen = r->updates_unstable = 0;
@@ -1264,7 +1288,7 @@ __rec_txn_read(WT_SESSION_IMPL *session, WT_RECONCILE *r,
 	WT_UPDATE *first_txn_upd, *first_upd, *upd;
 	wt_timestamp_t *timestampp;
 	size_t upd_memsize;
-	uint64_t max_txn, min_txn_unstable, txnid;
+	uint64_t max_txn, txnid;
 	bool all_visible, skipped_birthmark, uncommitted;
 
 #ifdef HAVE_TIMESTAMPS
@@ -1280,7 +1304,6 @@ __rec_txn_read(WT_SESSION_IMPL *session, WT_RECONCILE *r,
 	first_txn_upd = NULL;
 	upd_memsize = 0;
 	max_txn = WT_TXN_NONE;
-	min_txn_unstable = WT_TXN_ABORTED;
 	skipped_birthmark = uncommitted = false;
 
 	/*
@@ -1380,13 +1403,6 @@ __rec_txn_read(WT_SESSION_IMPL *session, WT_RECONCILE *r,
 			if (upd->type == WT_UPDATE_BIRTHMARK)
 				skipped_birthmark = true;
 
-			/*
-			 * Track minimum transaction ID for unstable updates.
-			 */
-			if (txnid != WT_TXN_NONE &&
-			    WT_TXNID_LT(txnid, min_txn_unstable))
-				min_txn_unstable = txnid;
-
 			continue;
 		}
 
@@ -1434,23 +1450,11 @@ __rec_txn_read(WT_SESSION_IMPL *session, WT_RECONCILE *r,
 	if (WT_TXNID_LT(r->max_txn, max_txn))
 		r->max_txn = max_txn;
 
-	/*
-	 * Track the oldest unstable transaction in the page. It is used to
-	 * decide whether to or not to read the history during a page read.
-	 */
-	if (WT_TXNID_LT(min_txn_unstable, r->min_txn_unstable))
-		r->min_txn_unstable = min_txn_unstable;
-
 #ifdef HAVE_TIMESTAMPS
 	/* Update the maximum timestamp. */
 	if (first_ts_upd != NULL &&
 	    __wt_timestamp_cmp(&r->max_timestamp, &first_ts_upd->timestamp) < 0)
 		__wt_timestamp_set(&r->max_timestamp, &first_ts_upd->timestamp);
-
-	/* Update the maximum on-page timestamp. */
-	if (upd != NULL &&
-	    __wt_timestamp_cmp(&upd->timestamp, &r->max_onpage_timestamp) > 0)
-		__wt_timestamp_set(&r->max_onpage_timestamp, &upd->timestamp);
 #endif
 
 	/*
@@ -1527,24 +1531,38 @@ __rec_txn_read(WT_SESSION_IMPL *session, WT_RECONCILE *r,
 	if (upd_savedp != NULL)
 		*upd_savedp = true;
 
+	/*
+	 * Track the first off-page update when saving history in the lookaside
+	 * table.  When skewing newest, we want the first (non-aborted) update
+	 * after the one stored on the page.  Otherwise, we want the update
+	 * before the on-page update.
+	 */
+	if (F_ISSET(r, WT_REC_LOOKASIDE) && r->las_skew_newest) {
+		if (WT_TXNID_LT(r->unstable_txn, first_upd->txnid))
+			r->unstable_txn = first_upd->txnid;
 #ifdef HAVE_TIMESTAMPS
-	/* Track the oldest saved timestamp for lookaside. */
-	if (F_ISSET(r, WT_REC_LOOKASIDE)) {
-		/* If no updates had timestamps, we're done. */
-		if (first_ts_upd == NULL)
-			__wt_timestamp_set_zero(&r->min_saved_timestamp);
+		if (first_ts_upd != NULL &&
+		    __wt_timestamp_cmp(&r->unstable_timestamp,
+		    &first_ts_upd->timestamp) < 0)
+			__wt_timestamp_set(&r->unstable_timestamp,
+			    &first_ts_upd->timestamp);
+#endif
+	} else if (F_ISSET(r, WT_REC_LOOKASIDE)) {
 		for (upd = first_upd; upd != *updp; upd = upd->next) {
-			if (upd->txnid != WT_TXN_ABORTED &&
-			    __wt_timestamp_cmp(&upd->timestamp,
-			    &r->min_saved_timestamp) < 0)
-				__wt_timestamp_set(&r->min_saved_timestamp,
-				    &upd->timestamp);
+			if (upd->txnid == WT_TXN_ABORTED)
+				continue;
 
-			WT_ASSERT(session, upd->txnid == WT_TXN_ABORTED ||
-			    WT_TXNID_LE(upd->txnid, r->max_txn));
+			if (upd->txnid != WT_TXN_NONE &&
+			    WT_TXNID_LT(upd->txnid, r->unstable_txn))
+				r->unstable_txn = upd->txnid;
+#ifdef HAVE_TIMESTAMPS
+			if (__wt_timestamp_cmp(&upd->timestamp,
+			    &r->unstable_timestamp) < 0)
+				__wt_timestamp_set(&r->unstable_timestamp,
+				    &upd->timestamp);
+#endif
 		}
 	}
-#endif
 
 check_original_value:
 	/*
@@ -3429,16 +3447,15 @@ __rec_split_write_supd(WT_SESSION_IMPL *session,
 
 done:	if (F_ISSET(r, WT_REC_LOOKASIDE)) {
 		/* Track the oldest lookaside timestamp seen so far. */
-		multi->page_las.las_skew_newest = r->las_skew_newest;
-		multi->page_las.las_max_txn = r->max_txn;
-		multi->page_las.las_min_txn = r->min_txn_unstable;
-		WT_ASSERT(session, r->max_txn != WT_TXN_NONE);
-		WT_ASSERT(session, r->min_txn_unstable != WT_TXN_NONE);
+		multi->page_las.skew_newest = r->las_skew_newest;
+		multi->page_las.max_txn = r->max_txn;
+		multi->page_las.unstable_txn = r->unstable_txn;
+		WT_ASSERT(session, r->unstable_txn != WT_TXN_NONE);
 #ifdef HAVE_TIMESTAMPS
-		__wt_timestamp_set(&multi->page_las.min_timestamp,
-		    &r->min_saved_timestamp);
-		__wt_timestamp_set(&multi->page_las.onpage_timestamp,
-		    &r->max_onpage_timestamp);
+		__wt_timestamp_set(&multi->page_las.max_timestamp,
+		    &r->max_timestamp);
+		__wt_timestamp_set(&multi->page_las.unstable_timestamp,
+		    &r->unstable_timestamp);
 #endif
 	}
 
diff --git a/src/third_party/wiredtiger/src/support/stat.c b/src/third_party/wiredtiger/src/support/stat.c
index 909019b3b24..0d39a5b682e 100644
--- a/src/third_party/wiredtiger/src/support/stat.c
+++ b/src/third_party/wiredtiger/src/support/stat.c
@@ -840,6 +840,7 @@ static const char * const __stats_connection_desc[] = {
 	"cache: maximum page size at eviction",
 	"cache: modified pages evicted",
 	"cache: modified pages evicted by application threads",
+	"cache: operations timed out waiting for space in cache",
 	"cache: overflow pages read into cache",
 	"cache: page split during eviction deepened the tree",
 	"cache: page written requiring lookaside records",
@@ -1097,6 +1098,7 @@ static const char * const __stats_connection_desc[] = {
 	"transaction: transaction range of IDs currently pinned by a checkpoint",
 	"transaction: transaction range of IDs currently pinned by named snapshots",
 	"transaction: transaction range of timestamps currently pinned",
+	"transaction: transaction range of timestamps pinned by a checkpoint",
 	"transaction: transaction range of timestamps pinned by the oldest timestamp",
 	"transaction: transaction sync calls",
 	"transaction: transactions committed",
@@ -1237,6 +1239,7 @@ __wt_stat_connection_clear_single(WT_CONNECTION_STATS *stats)
 		/* not clearing cache_eviction_maximum_page_size */
 	stats->cache_eviction_dirty = 0;
 	stats->cache_eviction_app_dirty = 0;
+	stats->cache_timed_out_ops = 0;
 	stats->cache_read_overflow = 0;
 	stats->cache_eviction_deepen = 0;
 	stats->cache_write_lookaside = 0;
@@ -1494,6 +1497,7 @@ __wt_stat_connection_clear_single(WT_CONNECTION_STATS *stats)
 		/* not clearing txn_pinned_checkpoint_range */
 		/* not clearing txn_pinned_snapshot_range */
 		/* not clearing txn_pinned_timestamp */
+		/* not clearing txn_pinned_timestamp_checkpoint */
 		/* not clearing txn_pinned_timestamp_oldest */
 	stats->txn_sync = 0;
 	stats->txn_commit = 0;
@@ -1662,6 +1666,7 @@ __wt_stat_connection_aggregate(
 	to->cache_eviction_dirty += WT_STAT_READ(from, cache_eviction_dirty);
 	to->cache_eviction_app_dirty +=
 	    WT_STAT_READ(from, cache_eviction_app_dirty);
+	to->cache_timed_out_ops += WT_STAT_READ(from, cache_timed_out_ops);
 	to->cache_read_overflow += WT_STAT_READ(from, cache_read_overflow);
 	to->cache_eviction_deepen +=
 	    WT_STAT_READ(from, cache_eviction_deepen);
@@ -2047,6 +2052,8 @@ __wt_stat_connection_aggregate(
 	to->txn_pinned_snapshot_range +=
 	    WT_STAT_READ(from, txn_pinned_snapshot_range);
 	to->txn_pinned_timestamp += WT_STAT_READ(from, txn_pinned_timestamp);
+	to->txn_pinned_timestamp_checkpoint +=
+	    WT_STAT_READ(from, txn_pinned_timestamp_checkpoint);
 	to->txn_pinned_timestamp_oldest +=
 	    WT_STAT_READ(from, txn_pinned_timestamp_oldest);
 	to->txn_sync += WT_STAT_READ(from, txn_sync);
diff --git a/src/third_party/wiredtiger/src/txn/txn.c b/src/third_party/wiredtiger/src/txn/txn.c
index cf233ab9a5d..4cb780c0042 100644
--- a/src/third_party/wiredtiger/src/txn/txn.c
+++ b/src/third_party/wiredtiger/src/txn/txn.c
@@ -119,9 +119,11 @@ void
 __wt_txn_release_snapshot(WT_SESSION_IMPL *session)
 {
 	WT_TXN *txn;
+	WT_TXN_GLOBAL *txn_global;
 	WT_TXN_STATE *txn_state;
 
 	txn = &session->txn;
+	txn_global = &S2C(session)->txn_global;
 	txn_state = WT_SESSION_TXN_STATE(session);
 
 	WT_ASSERT(session,
@@ -131,6 +133,14 @@ __wt_txn_release_snapshot(WT_SESSION_IMPL *session)
 
 	txn_state->metadata_pinned = txn_state->pinned_id = WT_TXN_NONE;
 	F_CLR(txn, WT_TXN_HAS_SNAPSHOT);
+
+	/* Clear a checkpoint's pinned ID. */
+	if (WT_SESSION_IS_CHECKPOINT(session)) {
+		txn_global->checkpoint_state.pinned_id = WT_TXN_NONE;
+		__wt_timestamp_set_zero(&txn_global->checkpoint_timestamp);
+	}
+
+	__wt_txn_clear_read_timestamp(session);
 }
 
 /*
@@ -528,8 +538,7 @@ __wt_txn_release(WT_SESSION_IMPL *session)
 	if (WT_SESSION_IS_CHECKPOINT(session)) {
 		WT_ASSERT(session,
 		    WT_SESSION_TXN_STATE(session)->id == WT_TXN_NONE);
-		txn->id = txn_global->checkpoint_state.id =
-		    txn_global->checkpoint_state.pinned_id = WT_TXN_NONE;
+		txn->id = txn_global->checkpoint_state.id = WT_TXN_NONE;
 
 		/*
 		 * Be extra careful to cleanup everything for checkpoints: once
@@ -548,7 +557,6 @@ __wt_txn_release(WT_SESSION_IMPL *session)
 	}
 
 	__wt_txn_clear_commit_timestamp(session);
-	__wt_txn_clear_read_timestamp(session);
 
 	/* Free the scratch buffer allocated for logging. */
 	__wt_logrec_free(session, &txn->logrec);
@@ -1283,12 +1291,24 @@ __wt_txn_stats_update(WT_SESSION_IMPL *session)
 	    txn_global->current - txn_global->oldest_id);
 
 #if WT_TIMESTAMP_SIZE == 8
+	{
+	WT_DECL_TIMESTAMP(checkpoint_timestamp)
+	WT_DECL_TIMESTAMP(commit_timestamp)
+	WT_DECL_TIMESTAMP(pinned_timestamp)
+
+	checkpoint_timestamp = txn_global->checkpoint_timestamp;
+	commit_timestamp = txn_global->commit_timestamp;
+	pinned_timestamp = txn_global->pinned_timestamp;
+	if (checkpoint_timestamp.val != 0 &&
+	    checkpoint_timestamp.val < pinned_timestamp.val)
+		pinned_timestamp = checkpoint_timestamp;
 	WT_STAT_SET(session, stats, txn_pinned_timestamp,
-	    txn_global->commit_timestamp.val -
-	    txn_global->pinned_timestamp.val);
+	    commit_timestamp.val - pinned_timestamp.val);
+	WT_STAT_SET(session, stats, txn_pinned_timestamp_checkpoint,
+	    commit_timestamp.val - checkpoint_timestamp.val);
 	WT_STAT_SET(session, stats, txn_pinned_timestamp_oldest,
-	    txn_global->commit_timestamp.val -
-	    txn_global->oldest_timestamp.val);
+	    commit_timestamp.val - txn_global->oldest_timestamp.val);
+	}
 #endif
 
 	WT_STAT_SET(session, stats, txn_pinned_snapshot_range,
diff --git a/src/third_party/wiredtiger/src/txn/txn_ckpt.c b/src/third_party/wiredtiger/src/txn/txn_ckpt.c
index b0ba6735056..ad8351923a0 100644
--- a/src/third_party/wiredtiger/src/txn/txn_ckpt.c
+++ b/src/third_party/wiredtiger/src/txn/txn_ckpt.c
@@ -372,12 +372,11 @@ __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 {
 	WT_CACHE *cache;
 	WT_CONNECTION_IMPL *conn;
-	double current_dirty, delta, scrub_min;
-	uint64_t bytes_written_last, bytes_written_start, bytes_written_total;
+	double current_dirty, prev_dirty;
+	uint64_t bytes_written_start, bytes_written_total;
 	uint64_t cache_size, max_write;
-	uint64_t current_us, stepdown_us, total_ms, work_us;
-	uint64_t time_last, time_start, time_stop;
-	bool progress;
+	uint64_t time_start, time_stop;
+	uint64_t total_ms;
 
 	conn = S2C(session);
 	cache = conn->cache;
@@ -388,61 +387,41 @@ __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 	 * scrubbing cannot help).
 	 */
 	if (F_ISSET(conn, WT_CONN_CLOSING_TIMESTAMP) ||
-	    cache->eviction_checkpoint_target < DBL_EPSILON ||
-	    cache->eviction_checkpoint_target >= cache->eviction_dirty_trigger)
+	    cache->eviction_checkpoint_target < DBL_EPSILON)
 		return;
 
-	time_last = time_start = __wt_clock(session);
-	bytes_written_last = 0;
+	time_start = __wt_clock(session);
 	bytes_written_start = cache->bytes_written;
-	cache_size = conn->cache_size;
+
 	/*
 	 * If the cache size is zero or very small, we're done.  The cache
 	 * size can briefly become zero if we're transitioning to a shared
 	 * cache via reconfigure.  This avoids potential divide by zero.
 	 */
-	if (cache_size < 10 * WT_MEGABYTE)
+	if ((cache_size = conn->cache_size) < 10 * WT_MEGABYTE)
 		return;
 
-	/*
-	 * Skip scrubbing if it won't perform at-least some minimum amount of
-	 * work. Scrubbing is supposed to bring down the dirty data to eviction
-	 * checkpoint target before the actual checkpoint starts. Do not perform
-	 * scrubbing if the dirty data to scrub is less than a pre-configured
-	 * size. This size is to an extent based on the configured cache size
-	 * without being too large or too small for large cache sizes. For the
-	 * values chosen, for instance, 100 GB cache will require at-least
-	 * 200 MB of dirty data above eviction checkpoint target, which should
-	 * equate to a scrub phase a few seconds long. That said, the value of
-	 * 0.2% and 500 MB are still somewhat arbitrary.
-	 */
-	scrub_min = WT_MIN((0.2 * conn->cache_size) / 100, 500 * WT_MEGABYTE);
-	if (__wt_cache_dirty_leaf_inuse(cache) <
-	    ((cache->eviction_checkpoint_target * conn->cache_size) / 100) +
-	    scrub_min)
+	current_dirty =
+	    (100.0 * __wt_cache_dirty_leaf_inuse(cache)) / cache_size;
+	if (current_dirty <= cache->eviction_checkpoint_target)
 		return;
 
-	stepdown_us = 10000;
-	work_us = 0;
-	progress = false;
-
-	/* Step down the scrub target (as a percentage) in units of 10MB. */
-	delta = WT_MIN(1.0, (100 * 10.0 * WT_MEGABYTE) / cache_size);
-
-	/*
-	 * Start with the scrub target equal to the expected maximum percentage
-	 * of dirty data in cache.
-	 */
-	cache->eviction_scrub_limit = cache->eviction_dirty_trigger;
-
 	/* Stop if we write as much dirty data as is currently in cache. */
 	max_write = __wt_cache_dirty_leaf_inuse(cache);
 
-	/* Step down the dirty target to the eviction trigger */
+	/* Set the dirty trigger to the target value. */
+	cache->eviction_scrub_target = cache->eviction_checkpoint_target;
+	WT_STAT_CONN_SET(session, txn_checkpoint_scrub_target, 0);
+
+	/* Wait while the dirty level is going down. */
 	for (;;) {
+		__wt_sleep(0, 100 * WT_THOUSAND);
+
+		prev_dirty = current_dirty;
 		current_dirty =
 		    (100.0 * __wt_cache_dirty_leaf_inuse(cache)) / cache_size;
-		if (current_dirty <= cache->eviction_checkpoint_target)
+		if (current_dirty <= cache->eviction_checkpoint_target ||
+		    current_dirty >= prev_dirty)
 			break;
 
 		/*
@@ -452,63 +431,17 @@ __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 		if (F_ISSET(cache, WT_CACHE_EVICT_LOOKASIDE))
 			break;
 
-		__wt_sleep(0, stepdown_us / 10);
-		time_stop = __wt_clock(session);
-		current_us = WT_CLOCKDIFF_US(time_stop, time_last);
-		bytes_written_total =
-		    cache->bytes_written - bytes_written_start;
-
-		if (current_dirty > cache->eviction_scrub_limit) {
-			/*
-			 * We haven't reached the current target.
-			 *
-			 * Don't wait indefinitely: there might be dirty pages
-			 * that can't be evicted.  If we can't meet the target,
-			 * give up and start the checkpoint for real.
-			 */
-			if (current_us > WT_MAX(WT_MILLION, 10 * stepdown_us) ||
-			    bytes_written_total > max_write)
-				break;
-			continue;
-		}
-
 		/*
-		 * Estimate how long the next step down of dirty data should
-		 * take.
-		 *
-		 * The calculation here assumes that the system is writing from
-		 * cache as fast as it can, and determines the write throughput
-		 * based on the change in the bytes written from cache since
-		 * the start of the call.  We use that to estimate how long it
-		 * will take to step the dirty target down by delta.
+		 * We haven't reached the current target.
 		 *
-		 * Take care to avoid dividing by zero.
-		 */
-		if (bytes_written_total - bytes_written_last > WT_MEGABYTE &&
-		    work_us > 0) {
-			stepdown_us = (uint64_t)((delta * cache_size / 100) /
-			    ((double)bytes_written_total / work_us));
-			stepdown_us = WT_MAX(1, stepdown_us);
-			if (!progress)
-				stepdown_us = WT_MIN(stepdown_us, 200000);
-			progress = true;
-
-			bytes_written_last = bytes_written_total;
-		}
-
-		work_us += current_us;
-
-		/*
-		 * Smooth out step down: try to limit the impact on
-		 * performance to 10% by waiting once we reach the last
-		 * level.
+		 * Don't wait indefinitely: there might be dirty pages
+		 * that can't be evicted.  If we can't meet the target,
+		 * give up and start the checkpoint for real.
 		 */
-		__wt_sleep(0, 10 * stepdown_us);
-		cache->eviction_scrub_limit =
-		    WT_MAX(cache->eviction_dirty_target, current_dirty - delta);
-		WT_STAT_CONN_SET(session, txn_checkpoint_scrub_target,
-		    cache->eviction_scrub_limit);
-		time_last = __wt_clock(session);
+		bytes_written_total =
+		    cache->bytes_written - bytes_written_start;
+		if (bytes_written_total > max_write)
+			break;
 	}
 
 	time_stop = __wt_clock(session);
@@ -681,8 +614,7 @@ __checkpoint_prepare(
 	 */
 	__wt_writelock(session, &txn_global->rwlock);
 	txn_global->checkpoint_state = *txn_state;
-	txn_global->checkpoint_txn = txn;
-	txn_global->checkpoint_state.pinned_id = WT_MIN(txn->id, txn->snap_min);
+	txn_global->checkpoint_state.pinned_id = txn->snap_min;
 
 	/*
 	 * Sanity check that the oldest ID hasn't moved on before we have
@@ -724,6 +656,8 @@ __checkpoint_prepare(
 		if (txn_global->has_stable_timestamp) {
 			__wt_timestamp_set(&txn->read_timestamp,
 			    &txn_global->stable_timestamp);
+			__wt_timestamp_set(&txn_global->checkpoint_timestamp,
+			    &txn->read_timestamp);
 			F_SET(txn, WT_TXN_HAS_TS_READ);
 			if (!F_ISSET(conn, WT_CONN_RECOVERING))
 				__wt_timestamp_set(
@@ -975,7 +909,7 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	 * Unblock updates -- we can figure out that any updates to clean pages
 	 * after this point are too new to be written in the checkpoint.
 	 */
-	cache->eviction_scrub_limit = 0.0;
+	cache->eviction_scrub_target = 0.0;
 	WT_STAT_CONN_SET(session, txn_checkpoint_scrub_target, 0);
 
 	/* Tell logging that we have started a database checkpoint. */
@@ -1125,7 +1059,7 @@ err:	/*
 	if (tracking)
 		WT_TRET(__wt_meta_track_off(session, false, failed));
 
-	cache->eviction_scrub_limit = 0.0;
+	cache->eviction_scrub_target = 0.0;
 	WT_STAT_CONN_SET(session, txn_checkpoint_scrub_target, 0);
 
 	if (F_ISSET(txn, WT_TXN_RUNNING)) {
diff --git a/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c b/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c
index 35a89eeb072..e01db53fda9 100644
--- a/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c
+++ b/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c
@@ -275,8 +275,9 @@ __txn_rollback_to_stable_btree_walk(
 	    WT_READ_CACHE | WT_READ_LOOKASIDE | WT_READ_NO_EVICT)) == 0 &&
 	    ref != NULL) {
 		if (ref->page_las != NULL &&
+		    ref->page_las->skew_newest &&
 		    __wt_timestamp_cmp(rollback_timestamp,
-		    &ref->page_las->onpage_timestamp) < 0)
+		    &ref->page_las->unstable_timestamp) < 0)
 			ref->page_las->invalid = true;
 
 		/* Review deleted page saved to the ref */
diff --git a/src/third_party/wiredtiger/src/txn/txn_timestamp.c b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
index a10ff740df6..64887c9a583 100644
--- a/src/third_party/wiredtiger/src/txn/txn_timestamp.c
+++ b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
@@ -193,6 +193,44 @@ __wt_txn_parse_timestamp(WT_SESSION_IMPL *session, const char *name,
 }
 
 /*
+ * __txn_get_pinned_timestamp --
+ *	Calculate the current pinned timestamp.
+ */
+static int
+__txn_get_pinned_timestamp(
+   WT_SESSION_IMPL *session, wt_timestamp_t *tsp, bool include_checkpoint)
+{
+	WT_CONNECTION_IMPL *conn;
+	WT_TXN *txn;
+	WT_TXN_GLOBAL *txn_global;
+
+	conn = S2C(session);
+	txn_global = &conn->txn_global;
+
+	if (!txn_global->has_oldest_timestamp)
+		return (WT_NOTFOUND);
+	__wt_readlock(session, &txn_global->rwlock);
+	__wt_timestamp_set(tsp, &txn_global->oldest_timestamp);
+
+	/* Check for a running checkpoint */
+	if (include_checkpoint &&
+	    !__wt_timestamp_iszero(&txn_global->checkpoint_timestamp) &&
+	    __wt_timestamp_cmp(&txn_global->checkpoint_timestamp, tsp) < 0)
+		__wt_timestamp_set(tsp, &txn_global->checkpoint_timestamp);
+	__wt_readunlock(session, &txn_global->rwlock);
+
+	/* Look for the oldest ordinary reader. */
+	__wt_readlock(session, &txn_global->read_timestamp_rwlock);
+	txn = TAILQ_FIRST(&txn_global->read_timestamph);
+	if (txn != NULL &&
+	    __wt_timestamp_cmp(&txn->read_timestamp, tsp) < 0)
+		__wt_timestamp_set(tsp, &txn->read_timestamp);
+	__wt_readunlock(session, &txn_global->read_timestamp_rwlock);
+
+	return (0);
+}
+
+/*
  * __txn_global_query_timestamp --
  *	Query a timestamp.
  */
@@ -248,26 +286,7 @@ __txn_global_query_timestamp(
 		WT_WITH_TIMESTAMP_READLOCK(session, &txn_global->rwlock,
 		    __wt_timestamp_set(&ts, &txn_global->oldest_timestamp));
 	} else if (WT_STRING_MATCH("pinned", cval.str, cval.len)) {
-		if (!txn_global->has_oldest_timestamp)
-			return (WT_NOTFOUND);
-		__wt_readlock(session, &txn_global->rwlock);
-		__wt_timestamp_set(&ts, &txn_global->oldest_timestamp);
-
-		/* Check for a running checkpoint */
-		txn = txn_global->checkpoint_txn;
-		if (txn_global->checkpoint_state.pinned_id != WT_TXN_NONE &&
-		    !__wt_timestamp_iszero(&txn->read_timestamp) &&
-		    __wt_timestamp_cmp(&txn->read_timestamp, &ts) < 0)
-			__wt_timestamp_set(&ts, &txn->read_timestamp);
-		__wt_readunlock(session, &txn_global->rwlock);
-
-		/* Look for the oldest ordinary reader. */
-		__wt_readlock(session, &txn_global->read_timestamp_rwlock);
-		txn = TAILQ_FIRST(&txn_global->read_timestamph);
-		if (txn != NULL &&
-		    __wt_timestamp_cmp(&txn->read_timestamp, &ts) < 0)
-			__wt_timestamp_set(&ts, &txn->read_timestamp);
-		__wt_readunlock(session, &txn_global->read_timestamp_rwlock);
+		WT_RET(__txn_get_pinned_timestamp(session, &ts, true));
 	} else if (WT_STRING_MATCH("recovery", cval.str, cval.len))
 		/* Read-only value forever. No lock needed. */
 		__wt_timestamp_set(&ts, &txn_global->recovery_timestamp);
@@ -320,8 +339,6 @@ __wt_txn_update_pinned_timestamp(WT_SESSION_IMPL *session, bool force)
 	WT_TXN_GLOBAL *txn_global;
 	wt_timestamp_t active_timestamp, last_pinned_timestamp;
 	wt_timestamp_t oldest_timestamp, pinned_timestamp;
-	const char *query_cfg[] = { WT_CONFIG_BASE(session,
-	    WT_CONNECTION_query_timestamp), "get=pinned", NULL };
 
 	txn_global = &S2C(session)->txn_global;
 
@@ -334,8 +351,8 @@ __wt_txn_update_pinned_timestamp(WT_SESSION_IMPL *session, bool force)
 	    &oldest_timestamp, &txn_global->oldest_timestamp));
 
 	/* Scan to find the global pinned timestamp. */
-	if ((ret = __txn_global_query_timestamp(
-	    session, &active_timestamp, query_cfg)) != 0)
+	if ((ret = __txn_get_pinned_timestamp(
+	    session, &active_timestamp, false)) != 0)
 		return (ret == WT_NOTFOUND ? 0 : ret);
 
 	if (__wt_timestamp_cmp(&oldest_timestamp, &active_timestamp) < 0) {
@@ -362,6 +379,9 @@ __wt_txn_update_pinned_timestamp(WT_SESSION_IMPL *session, bool force)
 		txn_global->oldest_is_pinned = __wt_timestamp_cmp(
 		    &txn_global->pinned_timestamp,
 		    &txn_global->oldest_timestamp) == 0;
+		txn_global->stable_is_pinned = __wt_timestamp_cmp(
+		    &txn_global->pinned_timestamp,
+		    &txn_global->stable_timestamp) == 0;
 		__wt_verbose_timestamp(session,
 		    &pinned_timestamp, "Updated pinned timestamp");
 	}
diff --git a/src/third_party/wiredtiger/test/format/config.h b/src/third_party/wiredtiger/test/format/config.h
index 51dc906465a..c398c1a96b2 100644
--- a/src/third_party/wiredtiger/test/format/config.h
+++ b/src/third_party/wiredtiger/test/format/config.h
@@ -331,41 +331,49 @@ static CONFIG c[] = {
 	  C_IGNORE, 0, 0, UINT_MAX, &g.c_timer, NULL },
 
 	{ "timing_stress_checkpoint",
-	  "configure slow checkpoints",				/* 2% */
+	  "stress checkpoints",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_checkpoint, NULL },
 
 	{ "timing_stress_lookaside_sweep",
-	  "configure slow lookaside sweep",			/* 2% */
+	  "stress lookaside sweep",				/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_lookaside_sweep, NULL },
 
 	{ "timing_stress_split_1",
-	  "configure slow splits (#1)",				/* 2% */
+	  "stress splits (#1)",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_1, NULL },
 
 	{ "timing_stress_split_2",
-	  "configure slow splits (#2)",				/* 2% */
+	  "stress splits (#2)",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_2, NULL },
 
 	{ "timing_stress_split_3",
-	  "configure slow splits (#3)",				/* 2% */
+	  "stress splits (#3)",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_3, NULL },
 
 	{ "timing_stress_split_4",
-	  "configure slow splits (#4)",				/* 2% */
+	  "stress splits (#4)",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_4, NULL },
 
 	{ "timing_stress_split_5",
-	  "configure slow splits (#5)",				/* 2% */
+	  "stress splits (#5)",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_5, NULL },
 
 	{ "timing_stress_split_6",
-	  "configure slow splits (#6)",				/* 2% */
+	  "stress splits (#6)",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_6, NULL },
 
 	{ "timing_stress_split_7",
-	  "configure slow splits (#7)",				/* 2% */
+	  "stress splits (#7)",					/* 2% */
 	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_7, NULL },
 
+	{ "timing_stress_split_8",
+	  "stress splits (#8)",					/* 2% */
+	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_8, NULL },
+
+	{ "timing_stress_split_9",
+	  "stress splits (#9)",					/* 2% */
+	  C_BOOL, 2, 0, 0, &g.c_timing_stress_split_9, NULL },
+
 	{ "transaction_timestamps",				/* 10% */
 	  "enable transaction timestamp support",
 	  C_BOOL, 10, 0, 0, &g.c_txn_timestamps, NULL },
diff --git a/src/third_party/wiredtiger/test/format/format.h b/src/third_party/wiredtiger/test/format/format.h
index 0eca6657dd9..1406d2b3fb5 100644
--- a/src/third_party/wiredtiger/test/format/format.h
+++ b/src/third_party/wiredtiger/test/format/format.h
@@ -221,6 +221,8 @@ typedef struct {
 	uint32_t c_timing_stress_split_5;
 	uint32_t c_timing_stress_split_6;
 	uint32_t c_timing_stress_split_7;
+	uint32_t c_timing_stress_split_8;
+	uint32_t c_timing_stress_split_9;
 	uint32_t c_truncate;
 	uint32_t c_txn_freq;
 	uint32_t c_txn_timestamps;
diff --git a/src/third_party/wiredtiger/test/format/lrt.c b/src/third_party/wiredtiger/test/format/lrt.c
index 9d99933ef64..31c5de93870 100644
--- a/src/third_party/wiredtiger/test/format/lrt.c
+++ b/src/third_party/wiredtiger/test/format/lrt.c
@@ -110,8 +110,15 @@ lrt(void *arg)
 			 */
 			testutil_check(session->snapshot(session, "name=test"));
 			__wt_sleep(1, 0);
-			testutil_check(session->begin_transaction(
-			    session, "snapshot=test"));
+			/*
+			 * Keep trying to start a new transaction if it's
+			 * timing out - we know there aren't any resources
+			 * pinned so it should succeed eventually.
+			 */
+			while ((ret = session->begin_transaction(
+			    session, "snapshot=test")) == WT_CACHE_FULL)
+				;
+			testutil_check(ret);
 			testutil_check(session->snapshot(
 			    session, "drop=(all)"));
 			testutil_check(session->commit_transaction(
@@ -123,8 +130,10 @@ lrt(void *arg)
 			 * positioned. As soon as the cursor loses its position
 			 * a new snapshot will be allocated.
 			 */
-			testutil_check(session->begin_transaction(
-			    session, "isolation=snapshot"));
+			while ((ret = session->begin_transaction(
+			    session, "snapshot=snapshot")) == WT_CACHE_FULL)
+				;
+			testutil_check(ret);
 
 			/* Read a record at the end of the table. */
 			do {
diff --git a/src/third_party/wiredtiger/test/format/ops.c b/src/third_party/wiredtiger/test/format/ops.c
index 7d08dbd8bd8..b3f5fd51ce2 100644
--- a/src/third_party/wiredtiger/test/format/ops.c
+++ b/src/third_party/wiredtiger/test/format/ops.c
@@ -498,6 +498,7 @@ static void
 begin_transaction(TINFO *tinfo, WT_SESSION *session, u_int *iso_configp)
 {
 	u_int v;
+	int ret;
 	const char *config;
 	char config_buf[64];
 	bool locked;
@@ -523,7 +524,15 @@ begin_transaction(TINFO *tinfo, WT_SESSION *session, u_int *iso_configp)
 	}
 	*iso_configp = v;
 
-	testutil_check(session->begin_transaction(session, config));
+	/*
+	 * Keep trying to start a new transaction if it's timing out - we
+	 * know there aren't any resources pinned so it should succeed
+	 * eventually.
+	 */
+	while ((ret =
+	    session->begin_transaction(session, config)) == WT_CACHE_FULL)
+		;
+	testutil_check(ret);
 
 	if (v == ISOLATION_SNAPSHOT && g.c_txn_timestamps) {
 		/* Avoid starting a new reader when a prepare is in progress. */
diff --git a/src/third_party/wiredtiger/test/format/wts.c b/src/third_party/wiredtiger/test/format/wts.c
index dd87adeae56..8040142aa19 100644
--- a/src/third_party/wiredtiger/test/format/wts.c
+++ b/src/third_party/wiredtiger/test/format/wts.c
@@ -262,6 +262,10 @@ wts_open(const char *home, bool set_api, WT_CONNECTION **connp)
 		CONFIG_APPEND(p, ",split_6");
 	if (g.c_timing_stress_split_7)
 		CONFIG_APPEND(p, ",split_7");
+	if (g.c_timing_stress_split_8)
+		CONFIG_APPEND(p, ",split_8");
+	if (g.c_timing_stress_split_9)
+		CONFIG_APPEND(p, ",split_9");
 	CONFIG_APPEND(p, "]");
 
 	/* Extensions. */
diff --git a/src/third_party/wiredtiger/test/suite/test_las03.py b/src/third_party/wiredtiger/test/suite/test_las03.py
new file mode 100644
index 00000000000..6934bd9a741
--- /dev/null
+++ b/src/third_party/wiredtiger/test/suite/test_las03.py
@@ -0,0 +1,105 @@
+#!/usr/bin/env python
+#
+# Public Domain 2014-2018 MongoDB, Inc.
+# Public Domain 2008-2014 WiredTiger, Inc.
+#
+# This is free and unencumbered software released into the public domain.
+#
+# Anyone is free to copy, modify, publish, use, compile, sell, or
+# distribute this software, either in source code form or as a compiled
+# binary, for any purpose, commercial or non-commercial, and by any
+# means.
+#
+# In jurisdictions that recognize copyright laws, the author or authors
+# of this software dedicate any and all copyright interest in the
+# software to the public domain. We make this dedication for the benefit
+# of the public at large and to the detriment of our heirs and
+# successors. We intend this dedication to be an overt act of
+# relinquishment in perpetuity of all present and future rights to this
+# software under copyright law.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+# OTHER DEALINGS IN THE SOFTWARE.
+
+from helper import copy_wiredtiger_home
+import wiredtiger, wttest
+from wiredtiger import stat
+from wtdataset import SimpleDataSet
+
+def timestamp_str(t):
+    return '%x' % t
+
+# test_las03.py
+# Ensure checkpoints don't read too unnecessary lookaside entries.
+class test_las03(wttest.WiredTigerTestCase):
+    # Force a small cache.
+    def conn_config(self):
+        return 'cache_size=50MB,statistics=(fast)'
+
+    def get_stat(self, stat):
+        stat_cursor = self.session.open_cursor('statistics:')
+        val = stat_cursor[stat][2]
+        stat_cursor.close()
+        return val
+
+    def large_updates(self, session, uri, value, ds, nrows, nops):
+        # Update a large number of records, we'll hang if the lookaside table
+        # isn't doing its thing.
+        cursor = session.open_cursor(uri)
+        for i in range(nrows + 1, nrows + nops + 1):
+            session.begin_transaction()
+            cursor[ds.key(i)] = value
+            session.commit_transaction('commit_timestamp=' + timestamp_str(i))
+        cursor.close()
+
+    def test_checkpoint_las_reads(self):
+        if not wiredtiger.timestamp_build():
+            self.skipTest('requires a timestamp build')
+
+        # Create a small table.
+        uri = "table:test_las03"
+        nrows = 100
+        ds = SimpleDataSet(self, uri, nrows, key_format="S", value_format='u')
+        ds.populate()
+        bigvalue = "aaaaa" * 100
+
+        # Initially load huge data
+        cursor = self.session.open_cursor(uri)
+        for i in range(1, 10000):
+            cursor[ds.key(nrows + i)] = bigvalue
+        cursor.close()
+        self.session.checkpoint()
+
+        # Check to see LAS working with old timestamp
+        bigvalue2 = "ddddd" * 100
+        self.conn.set_timestamp('stable_timestamp=' + timestamp_str(1))
+        las_writes_start = self.get_stat(stat.conn.cache_write_lookaside)
+        self.large_updates(self.session, uri, bigvalue2, ds, nrows, 10000)
+
+        # If the test sizing is correct, the history will overflow the cache
+        self.session.checkpoint()
+        las_writes = self.get_stat(stat.conn.cache_write_lookaside) - las_writes_start
+        self.assertGreaterEqual(las_writes, 0)
+
+        for ts in range(2, 4):
+            self.conn.set_timestamp('stable_timestamp=' + timestamp_str(ts))
+
+            # Now just update one record and checkpoint again
+            self.large_updates(self.session, uri, bigvalue2, ds, nrows, 1)
+
+            las_reads_start = self.get_stat(stat.conn.cache_read_lookaside)
+            self.session.checkpoint()
+            las_reads = self.get_stat(stat.conn.cache_read_lookaside) - las_reads_start
+
+            # Since we're dealing with eviction concurrent with checkpoints
+            # and skewing is controlled by a heuristic, we can't put too tight
+            # a bound on this.
+            self.assertLessEqual(las_reads, 100)
+
+if __name__ == '__main__':
+    wttest.run()