Import wiredtiger: b33708d7d9b2971cda05e71fcba6067b230b97cc from branch mongodb-3.8

ref: 60a06941b8..b33708d7d9
for: 3.7.4

WT-3913       Enhance cursor operations to account for prepare state
WT-3950       Add some rollback_to_stable statistics
WT-3958       Add query API to get most recent checkpoint's stable timestamp
WT-3969       enhance format tester to account for prepare state
WT-3972       Allow more than 64K cursors to be open on a data source simultaneously
WT-3975       arg format mismatch after rwlock changes

31 files changed, 759 insertions, 438 deletions

diff --git a/src/third_party/wiredtiger/dist/api_data.py b/src/third_party/wiredtiger/dist/api_data.py
index 17fe0d97735..f5e0b4a67a3 100644
--- a/src/third_party/wiredtiger/dist/api_data.py
+++ b/src/third_party/wiredtiger/dist/api_data.py
@@ -1371,7 +1371,8 @@ methods = {
         \c oldest_timestamp and the read timestamps of all active readers, and
         \c stable returns the most recent \c stable_timestamp set with
         WT_CONNECTION::set_timestamp.  See @ref transaction_timestamps''',
-        choices=['all_committed','oldest','pinned','recovery','stable']),
+        choices=['all_committed','last_checkpoint',
+            'oldest','pinned','recovery','stable']),
 ]),
 
 'WT_CONNECTION.set_timestamp' : Method([
diff --git a/src/third_party/wiredtiger/dist/stat_data.py b/src/third_party/wiredtiger/dist/stat_data.py
index a630ebe3fa9..1441187812e 100644
--- a/src/third_party/wiredtiger/dist/stat_data.py
+++ b/src/third_party/wiredtiger/dist/stat_data.py
@@ -518,6 +518,9 @@ connection_stats = [
     TxnStat('txn_read_queue_inserts', 'read timestamp queue inserts total'),
     TxnStat('txn_read_queue_len', 'read timestamp queue length'),
     TxnStat('txn_rollback', 'transactions rolled back'),
+    TxnStat('txn_rollback_las_removed', 'rollback to stable updates removed from lookaside'),
+    TxnStat('txn_rollback_to_stable', 'rollback to stable calls'),
+    TxnStat('txn_rollback_upd_aborted', 'rollback to stable updates aborted'),
     TxnStat('txn_set_ts', 'set timestamp calls'),
     TxnStat('txn_set_ts_commit', 'set timestamp commit calls'),
     TxnStat('txn_set_ts_commit_upd', 'set timestamp commit updates'),
diff --git a/src/third_party/wiredtiger/import.data b/src/third_party/wiredtiger/import.data
index 16374d1697a..53642b757b5 100644
--- a/src/third_party/wiredtiger/import.data
+++ b/src/third_party/wiredtiger/import.data
@@ -1,5 +1,5 @@
 {
-    "commit": "60a06941b8d5d7ddc9f93646e75fc4b52d40f9b4", 
+    "commit": "b33708d7d9b2971cda05e71fcba6067b230b97cc", 
     "github": "wiredtiger/wiredtiger.git", 
     "vendor": "wiredtiger", 
     "branch": "mongodb-3.8"
diff --git a/src/third_party/wiredtiger/src/btree/bt_curnext.c b/src/third_party/wiredtiger/src/btree/bt_curnext.c
index 6737af9996b..63d2cda4714 100644
--- a/src/third_party/wiredtiger/src/btree/bt_curnext.c
+++ b/src/third_party/wiredtiger/src/btree/bt_curnext.c
@@ -54,12 +54,17 @@ __cursor_fix_append_next(WT_CURSOR_BTREE *cbt, bool newpage)
 	 * insert is aborted, we simply return zero (empty), regardless of
 	 * whether we are at the end of the data.
 	 */
-	if (cbt->recno < WT_INSERT_RECNO(cbt->ins) ||
-	    (upd = __wt_txn_read(session, cbt->ins->upd)) == NULL) {
+	if (cbt->recno < WT_INSERT_RECNO(cbt->ins)) {
 		cbt->v = 0;
 		cbt->iface.value.data = &cbt->v;
-	} else
-		cbt->iface.value.data = upd->data;
+	} else {
+		WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
+		if (upd == NULL) {
+			cbt->v = 0;
+			cbt->iface.value.data = &cbt->v;
+		} else
+			cbt->iface.value.data = upd->data;
+	}
 	cbt->iface.value.size = 1;
 	return (0);
 }
@@ -79,6 +84,7 @@ __cursor_fix_next(WT_CURSOR_BTREE *cbt, bool newpage)
 	session = (WT_SESSION_IMPL *)cbt->iface.session;
 	btree = S2BT(session);
 	page = cbt->ref->page;
+	upd = NULL;
 
 	/* Initialize for each new page. */
 	if (newpage) {
@@ -101,7 +107,8 @@ new_page:
 	    cbt->ins_head, cbt->ins_stack, cbt->next_stack, cbt->recno);
 	if (cbt->ins != NULL && cbt->recno != WT_INSERT_RECNO(cbt->ins))
 		cbt->ins = NULL;
-	upd = cbt->ins == NULL ? NULL : __wt_txn_read(session, cbt->ins->upd);
+	if (cbt->ins != NULL)
+		WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
 	if (upd == NULL) {
 		cbt->v = __bit_getv_recno(cbt->ref, cbt->recno, btree->bitcnt);
 		cbt->iface.value.data = &cbt->v;
@@ -134,7 +141,8 @@ new_page:	if (cbt->ins == NULL)
 			return (WT_NOTFOUND);
 
 		__cursor_set_recno(cbt, WT_INSERT_RECNO(cbt->ins));
-		if ((upd = __wt_txn_read(session, cbt->ins->upd)) == NULL)
+		WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
+		if (upd == NULL)
 			continue;
 		if (upd->type == WT_UPDATE_TOMBSTONE) {
 			if (upd->txnid != WT_TXN_NONE &&
@@ -193,8 +201,9 @@ new_page:	/* Find the matching WT_COL slot. */
 		/* Check any insert list for a matching record. */
 		cbt->ins_head = WT_COL_UPDATE_SLOT(page, cbt->slot);
 		cbt->ins = __col_insert_search_match(cbt->ins_head, cbt->recno);
-		upd = cbt->ins == NULL ?
-		    NULL : __wt_txn_read(session, cbt->ins->upd);
+		upd = NULL;
+		if (cbt->ins != NULL)
+			WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
 		if (upd != NULL) {
 			if (upd->type == WT_UPDATE_TOMBSTONE) {
 				if (upd->txnid != WT_TXN_NONE &&
@@ -311,7 +320,8 @@ __cursor_row_next(WT_CURSOR_BTREE *cbt, bool newpage)
 			cbt->ins = WT_SKIP_NEXT(cbt->ins);
 
 new_insert:	if ((ins = cbt->ins) != NULL) {
-			if ((upd = __wt_txn_read(session, ins->upd)) == NULL)
+			WT_RET(__wt_txn_read(session, ins->upd, &upd));
+			if (upd == NULL)
 				continue;
 			if (upd->type == WT_UPDATE_TOMBSTONE) {
 				if (upd->txnid != WT_TXN_NONE &&
@@ -344,7 +354,7 @@ new_insert:	if ((ins = cbt->ins) != NULL) {
 
 		cbt->slot = cbt->row_iteration_slot / 2 - 1;
 		rip = &page->pg_row[cbt->slot];
-		upd = __wt_txn_read(session, WT_ROW_UPDATE(page, rip));
+		WT_RET(__wt_txn_read(session, WT_ROW_UPDATE(page, rip), &upd));
 		if (upd != NULL && upd->type == WT_UPDATE_TOMBSTONE) {
 			if (upd->txnid != WT_TXN_NONE &&
 			    __wt_txn_upd_visible_all(session, upd))
@@ -571,8 +581,9 @@ __wt_btcur_next(WT_CURSOR_BTREE *cbt, bool truncating)
 	WT_DECL_RET;
 	WT_PAGE *page;
 	WT_SESSION_IMPL *session;
+	WT_UPDATE *upd;
 	uint32_t flags;
-	bool newpage;
+	bool newpage, valid;
 
 	cursor = &cbt->iface;
 	session = (WT_SESSION_IMPL *)cbt->iface.session;
@@ -582,6 +593,26 @@ __wt_btcur_next(WT_CURSOR_BTREE *cbt, bool truncating)
 
 	F_CLR(cursor, WT_CURSTD_KEY_SET | WT_CURSTD_VALUE_SET);
 
+	/*
+	 * In case of retrying a next operation due to a prepare conflict,
+	 * cursor would have been already positioned at an update structure
+	 * which resulted in conflict. So, now when retrying we should examine
+	 * the same update again instead of starting from the next one in the
+	 * update chain.
+	 */
+	F_CLR(cbt, WT_CBT_RETRY_PREV);
+	if (F_ISSET(cbt, WT_CBT_RETRY_NEXT)) {
+		WT_RET(__wt_cursor_valid(cbt, &upd, &valid));
+		F_CLR(cbt, WT_CBT_RETRY_NEXT);
+		if (valid) {
+			/*
+			 * If the update, which returned prepared conflict is
+			 * visible, return the value.
+			 */
+			return (__cursor_kv_return(session, cbt, upd));
+		}
+	}
+
 	WT_RET(__cursor_func_init(cbt, false));
 
 	/*
@@ -663,15 +694,24 @@ __wt_btcur_next(WT_CURSOR_BTREE *cbt, bool truncating)
 		WT_ERR(__wt_tree_walk(session, &cbt->ref, flags));
 		WT_ERR_TEST(cbt->ref == NULL, WT_NOTFOUND);
 	}
-
 #ifdef HAVE_DIAGNOSTIC
 	if (ret == 0)
 		WT_ERR(__wt_cursor_key_order_check(session, cbt, true));
 #endif
-	if (ret == 0)
+err:	switch (ret) {
+	case 0:
 		F_SET(cursor, WT_CURSTD_KEY_INT | WT_CURSTD_VALUE_INT);
-
-err:	if (ret != 0)
+		break;
+	case WT_PREPARE_CONFLICT:
+		/*
+		 * If prepare conflict occurs, cursor should not be reset,
+		 * as current cursor position will be reused in case of a
+		 * retry from user.
+		 */
+		F_SET(cbt, WT_CBT_RETRY_NEXT);
+		break;
+	default:
 		WT_TRET(__cursor_reset(cbt));
+	}
 	return (ret);
 }
diff --git a/src/third_party/wiredtiger/src/btree/bt_curprev.c b/src/third_party/wiredtiger/src/btree/bt_curprev.c
index 068a9915ab9..3356baeb24a 100644
--- a/src/third_party/wiredtiger/src/btree/bt_curprev.c
+++ b/src/third_party/wiredtiger/src/btree/bt_curprev.c
@@ -199,13 +199,18 @@ __cursor_fix_append_prev(WT_CURSOR_BTREE *cbt, bool newpage)
 	 * created records written by reconciliation are deleted and so can be
 	 * never seen by a read.
 	 */
-	if (cbt->ins == NULL ||
-	    cbt->recno > WT_INSERT_RECNO(cbt->ins) ||
-	    (upd = __wt_txn_read(session, cbt->ins->upd)) == NULL) {
+	if (cbt->ins == NULL || cbt->recno > WT_INSERT_RECNO(cbt->ins)) {
 		cbt->v = 0;
 		cbt->iface.value.data = &cbt->v;
-	} else
-		cbt->iface.value.data = upd->data;
+	} else {
+		upd = NULL;
+		WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
+		if (upd == NULL) {
+			cbt->v = 0;
+			cbt->iface.value.data = &cbt->v;
+		} else
+			cbt->iface.value.data = upd->data;
+	}
 	cbt->iface.value.size = 1;
 	return (0);
 }
@@ -247,7 +252,9 @@ new_page:
 	    cbt->ins_head, cbt->ins_stack, cbt->next_stack, cbt->recno);
 	if (cbt->ins != NULL && cbt->recno != WT_INSERT_RECNO(cbt->ins))
 		cbt->ins = NULL;
-	upd = cbt->ins == NULL ? NULL : __wt_txn_read(session, cbt->ins->upd);
+	upd = NULL;
+	if (cbt->ins != NULL)
+		WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
 	if (upd == NULL) {
 		cbt->v = __bit_getv_recno(cbt->ref, cbt->recno, btree->bitcnt);
 		cbt->iface.value.data = &cbt->v;
@@ -280,7 +287,8 @@ new_page:	if (cbt->ins == NULL)
 			return (WT_NOTFOUND);
 
 		__cursor_set_recno(cbt, WT_INSERT_RECNO(cbt->ins));
-		if ((upd = __wt_txn_read(session, cbt->ins->upd)) == NULL)
+		WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
+		if (upd == NULL)
 			continue;
 		if (upd->type == WT_UPDATE_TOMBSTONE) {
 			if (upd->txnid != WT_TXN_NONE &&
@@ -340,8 +348,9 @@ new_page:	if (cbt->recno < cbt->ref->ref_recno)
 		/* Check any insert list for a matching record. */
 		cbt->ins_head = WT_COL_UPDATE_SLOT(page, cbt->slot);
 		cbt->ins = __col_insert_search_match(cbt->ins_head, cbt->recno);
-		upd = cbt->ins == NULL ?
-		    NULL : __wt_txn_read(session, cbt->ins->upd);
+		upd = NULL;
+		if (cbt->ins != NULL)
+			WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
 		if (upd != NULL) {
 			if (upd->type == WT_UPDATE_TOMBSTONE) {
 				if (upd->txnid != WT_TXN_NONE &&
@@ -468,7 +477,8 @@ __cursor_row_prev(WT_CURSOR_BTREE *cbt, bool newpage)
 			WT_RET(__cursor_skip_prev(cbt));
 
 new_insert:	if ((ins = cbt->ins) != NULL) {
-			if ((upd = __wt_txn_read(session, ins->upd)) == NULL)
+			WT_RET(__wt_txn_read(session, ins->upd, &upd));
+			if (upd == NULL)
 				continue;
 			if (upd->type == WT_UPDATE_TOMBSTONE) {
 				if (upd->txnid != WT_TXN_NONE &&
@@ -503,7 +513,7 @@ new_insert:	if ((ins = cbt->ins) != NULL) {
 
 		cbt->slot = cbt->row_iteration_slot / 2 - 1;
 		rip = &page->pg_row[cbt->slot];
-		upd = __wt_txn_read(session, WT_ROW_UPDATE(page, rip));
+		WT_RET(__wt_txn_read(session, WT_ROW_UPDATE(page, rip), &upd));
 		if (upd != NULL && upd->type == WT_UPDATE_TOMBSTONE) {
 			if (upd->txnid != WT_TXN_NONE &&
 			    __wt_txn_upd_visible_all(session, upd))
@@ -526,8 +536,9 @@ __wt_btcur_prev(WT_CURSOR_BTREE *cbt, bool truncating)
 	WT_DECL_RET;
 	WT_PAGE *page;
 	WT_SESSION_IMPL *session;
+	WT_UPDATE *upd;
 	uint32_t flags;
-	bool newpage;
+	bool newpage, valid;
 
 	cursor = &cbt->iface;
 	session = (WT_SESSION_IMPL *)cbt->iface.session;
@@ -537,6 +548,26 @@ __wt_btcur_prev(WT_CURSOR_BTREE *cbt, bool truncating)
 
 	F_CLR(cursor, WT_CURSTD_KEY_SET | WT_CURSTD_VALUE_SET);
 
+	/*
+	 * In case of retrying a prev operation due to a prepare conflict,
+	 * cursor would have been already positioned at an update structure
+	 * which resulted in conflict. So, now when retrying we should examine
+	 * the same update again instead of starting from the next one in the
+	 * update chain.
+	 */
+	F_CLR(cbt, WT_CBT_RETRY_NEXT);
+	if (F_ISSET(cbt, WT_CBT_RETRY_PREV)) {
+		WT_RET(__wt_cursor_valid(cbt, &upd, &valid));
+		F_CLR(cbt, WT_CBT_RETRY_PREV);
+		if (valid) {
+			/*
+			 * If the update, which returned prepared conflict is
+			 * visible, return the value.
+			 */
+			return (__cursor_kv_return(session, cbt, upd));
+		}
+	}
+
 	WT_RET(__cursor_func_init(cbt, false));
 
 	/*
@@ -622,10 +653,20 @@ __wt_btcur_prev(WT_CURSOR_BTREE *cbt, bool truncating)
 	if (ret == 0)
 		WT_ERR(__wt_cursor_key_order_check(session, cbt, false));
 #endif
-	if (ret == 0)
+err:	switch (ret) {
+	case 0:
 		F_SET(cursor, WT_CURSTD_KEY_INT | WT_CURSTD_VALUE_INT);
-
-err:	if (ret != 0)
+		break;
+	case WT_PREPARE_CONFLICT:
+		/*
+		 * If prepare conflict occurs, cursor should not be reset,
+		 * as current cursor position will be reused in case of a
+		 * retry from user.
+		 */
+		F_SET(cbt, WT_CBT_RETRY_PREV);
+		break;
+	default:
 		WT_TRET(__cursor_reset(cbt));
+	}
 	return (ret);
 }
diff --git a/src/third_party/wiredtiger/src/btree/bt_cursor.c b/src/third_party/wiredtiger/src/btree/bt_cursor.c
index 29725e22b2c..bf535896c73 100644
--- a/src/third_party/wiredtiger/src/btree/bt_cursor.c
+++ b/src/third_party/wiredtiger/src/btree/bt_cursor.c
@@ -205,8 +205,8 @@ __cursor_fix_implicit(WT_BTREE *btree, WT_CURSOR_BTREE *cbt)
  * __wt_cursor_valid --
  *	Return if the cursor references an valid key/value pair.
  */
-bool
-__wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
+int
+__wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp, bool *valid)
 {
 	WT_BTREE *btree;
 	WT_CELL *cell;
@@ -215,11 +215,12 @@ __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
 	WT_SESSION_IMPL *session;
 	WT_UPDATE *upd;
 
+	if (updp != NULL)
+		*updp = NULL;
+	*valid = false;
 	btree = cbt->btree;
 	page = cbt->ref->page;
 	session = (WT_SESSION_IMPL *)cbt->iface.session;
-	if (updp != NULL)
-		*updp = NULL;
 
 	/*
 	 * We may be pointing to an insert object, and we may have a page with
@@ -265,13 +266,16 @@ __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
 	 * First, check for an insert object with a visible update (a visible
 	 * update that's been deleted is not a valid key/value pair).
 	 */
-	if (cbt->ins != NULL &&
-	    (upd = __wt_txn_read(session, cbt->ins->upd)) != NULL) {
-		if (upd->type == WT_UPDATE_TOMBSTONE)
-			return (false);
-		if (updp != NULL)
-			*updp = upd;
-		return (true);
+	if (cbt->ins != NULL) {
+		WT_RET(__wt_txn_read(session, cbt->ins->upd, &upd));
+		if (upd != NULL) {
+			if (upd->type == WT_UPDATE_TOMBSTONE)
+				return (0);
+			if (updp != NULL)
+				*updp = upd;
+			*valid = true;
+			return (0);
+		}
 	}
 
 	/*
@@ -290,7 +294,7 @@ __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
 		 * keys, check for retrieval past the end of the page.
 		 */
 		if (cbt->recno >= cbt->ref->ref_recno + page->entries)
-			return (false);
+			return (0);
 
 		/*
 		 * An update would have appeared as an "insert" object; no
@@ -300,7 +304,7 @@ __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
 	case BTREE_COL_VAR:
 		/* The search function doesn't check for empty pages. */
 		if (page->entries == 0)
-			return (false);
+			return (0);
 		WT_ASSERT(session, cbt->slot < page->entries);
 
 		/*
@@ -309,7 +313,7 @@ __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
 		 * returned on-page object must be checked for a match.
 		 */
 		if (cbt->ins != NULL && !F_ISSET(cbt, WT_CBT_VAR_ONPAGE_MATCH))
-			return (false);
+			return (0);
 
 		/*
 		 * Although updates would have appeared as an "insert" objects,
@@ -320,12 +324,12 @@ __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
 		cip = &page->pg_var[cbt->slot];
 		if ((cell = WT_COL_PTR(page, cip)) == NULL ||
 		    __wt_cell_type(cell) == WT_CELL_DEL)
-			return (false);
+			return (0);
 		break;
 	case BTREE_ROW:
 		/* The search function doesn't check for empty pages. */
 		if (page->entries == 0)
-			return (false);
+			return (0);
 		WT_ASSERT(session, cbt->slot < page->entries);
 
 		/*
@@ -333,34 +337,23 @@ __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp)
 		 * key as an on-page object, we're done.
 		 */
 		if (cbt->ins != NULL)
-			return (false);
+			return (0);
 
 		/* Check for an update. */
 		if (page->modify != NULL &&
-		    page->modify->mod_row_update != NULL &&
-		    (upd = __wt_txn_read(session,
-		    page->modify->mod_row_update[cbt->slot])) != NULL) {
-			if (upd->type == WT_UPDATE_TOMBSTONE)
-				return (false);
-			if (updp != NULL)
-				*updp = upd;
+		    page->modify->mod_row_update != NULL) {
+			WT_RET(__wt_txn_read(session,
+			    page->modify->mod_row_update[cbt->slot], &upd));
+			if (upd != NULL) {
+				if (upd->type == WT_UPDATE_TOMBSTONE)
+					return (0);
+				if (updp != NULL)
+					*updp = upd;
+			}
 		}
 		break;
 	}
-	return (true);
-}
-
-/*
- * __cursor_kv_return --
- *	Return a page referenced key/value pair to the application.
- */
-static inline int
-__cursor_kv_return(
-    WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_UPDATE *upd)
-{
-	WT_RET(__wt_key_return(session, cbt));
-	WT_RET(__wt_value_return(session, cbt, upd));
-
+	*valid = true;
 	return (0);
 }
 
@@ -512,7 +505,10 @@ __wt_btcur_search(WT_CURSOR_BTREE *cbt)
 		WT_ERR(btree->type == BTREE_ROW ?
 		    __cursor_row_search(session, cbt, cbt->ref, false) :
 		    __cursor_col_search(session, cbt, cbt->ref));
-		valid = cbt->compare == 0 && __wt_cursor_valid(cbt, &upd);
+
+		/* Return, if prepare conflict encountered. */
+		if (cbt->compare == 0)
+			WT_ERR(__wt_cursor_valid(cbt, &upd, &valid));
 	}
 	if (!valid) {
 		WT_ERR(__cursor_func_init(cbt, true));
@@ -520,7 +516,10 @@ __wt_btcur_search(WT_CURSOR_BTREE *cbt)
 		WT_ERR(btree->type == BTREE_ROW ?
 		    __cursor_row_search(session, cbt, NULL, false) :
 		    __cursor_col_search(session, cbt, NULL));
-		valid = cbt->compare == 0 && __wt_cursor_valid(cbt, &upd);
+
+		/* Return, if prepare conflict encountered. */
+		if (cbt->compare == 0)
+			WT_ERR(__wt_cursor_valid(cbt, &upd, &valid));
 	}
 
 	if (valid)
@@ -618,14 +617,14 @@ __wt_btcur_search_near(WT_CURSOR_BTREE *cbt, int *exactp)
 		 * Ignore those cases, it makes things too complicated.
 		 */
 		if (cbt->slot != 0 && cbt->slot != cbt->ref->page->entries - 1)
-			valid = __wt_cursor_valid(cbt, &upd);
+			WT_ERR(__wt_cursor_valid(cbt, &upd, &valid));
 	}
 	if (!valid) {
 		WT_ERR(__cursor_func_init(cbt, true));
 		WT_ERR(btree->type == BTREE_ROW ?
 		    __cursor_row_search(session, cbt, NULL, true) :
 		    __cursor_col_search(session, cbt, NULL));
-		valid = __wt_cursor_valid(cbt, &upd);
+		WT_ERR(__wt_cursor_valid(cbt, &upd, &valid));
 	}
 
 	/*
@@ -656,9 +655,10 @@ __wt_btcur_search_near(WT_CURSOR_BTREE *cbt, int *exactp)
 		exact = 0;
 		F_CLR(cursor, WT_CURSTD_KEY_SET | WT_CURSTD_VALUE_SET);
 		F_SET(cursor, WT_CURSTD_KEY_INT | WT_CURSTD_VALUE_INT);
-	} else if ((ret = __wt_btcur_next(cbt, false)) != WT_NOTFOUND)
+	} else if ((ret = __wt_btcur_next(cbt, false)) != WT_NOTFOUND) {
+		WT_ERR(ret);
 		exact = 1;
-	else {
+	} else {
 		/*
 		 * The cursor next call may have overwritten our caller's key,
 		 * restore it to its original value.
@@ -669,11 +669,14 @@ __wt_btcur_search_near(WT_CURSOR_BTREE *cbt, int *exactp)
 		WT_ERR(btree->type == BTREE_ROW ?
 		    __cursor_row_search(session, cbt, NULL, true) :
 		    __cursor_col_search(session, cbt, NULL));
-		if (__wt_cursor_valid(cbt, &upd)) {
+		WT_ERR(__wt_cursor_valid(cbt, &upd, &valid));
+		if (valid) {
 			exact = cbt->compare;
 			ret = __cursor_kv_return(session, cbt, upd);
-		} else if ((ret = __wt_btcur_prev(cbt, false)) != WT_NOTFOUND)
+		} else if ((ret = __wt_btcur_prev(cbt, false)) != WT_NOTFOUND) {
+			WT_ERR(ret);
 			exact = -1;
+		}
 	}
 
 err:	if (ret == 0 && exactp != NULL)
@@ -703,7 +706,7 @@ __wt_btcur_insert(WT_CURSOR_BTREE *cbt)
 	WT_CURSOR *cursor;
 	WT_DECL_RET;
 	WT_SESSION_IMPL *session;
-	bool append_key;
+	bool append_key, valid;
 
 	btree = cbt->btree;
 	cursor = &cbt->iface;
@@ -784,8 +787,11 @@ retry:	WT_ERR(__cursor_func_init(cbt, true));
 		 * key/value pair.
 		 */
 		if (!F_ISSET(cursor, WT_CURSTD_OVERWRITE) &&
-		    cbt->compare == 0 && __wt_cursor_valid(cbt, NULL))
-			WT_ERR(WT_DUPLICATE_KEY);
+		    cbt->compare == 0) {
+			WT_ERR(__wt_cursor_valid(cbt, NULL, &valid));
+			if (valid)
+				WT_ERR(WT_DUPLICATE_KEY);
+		}
 
 		ret = __cursor_row_modify(session, cbt, WT_UPDATE_STANDARD);
 	} else {
@@ -805,10 +811,14 @@ retry:	WT_ERR(__cursor_func_init(cbt, true));
 		 * column-store implicitly fills the gap with empty records.
 		 * Fail in that case, the record exists.
 		 */
-		if (!F_ISSET(cursor, WT_CURSTD_OVERWRITE) &&
-		    ((cbt->compare == 0 && __wt_cursor_valid(cbt, NULL)) ||
-		    (cbt->compare != 0 && __cursor_fix_implicit(btree, cbt))))
-			WT_ERR(WT_DUPLICATE_KEY);
+		if (!F_ISSET(cursor, WT_CURSTD_OVERWRITE)) {
+			if (cbt->compare == 0) {
+				WT_ERR(__wt_cursor_valid(cbt, NULL, &valid));
+				if (valid)
+					WT_ERR(WT_DUPLICATE_KEY);
+			} else if (__cursor_fix_implicit(btree, cbt))
+				WT_ERR(WT_DUPLICATE_KEY);
+		}
 
 		WT_ERR(__cursor_col_modify(session, cbt, WT_UPDATE_STANDARD));
 
@@ -932,7 +942,7 @@ __wt_btcur_remove(WT_CURSOR_BTREE *cbt)
 	WT_CURSOR *cursor;
 	WT_DECL_RET;
 	WT_SESSION_IMPL *session;
-	bool iterating;
+	bool iterating, valid;
 
 	btree = cbt->btree;
 	cursor = &cbt->iface;
@@ -1028,7 +1038,10 @@ retry:	if (positioned == POSITIONED)
 		/* Check whether an update would conflict. */
 		WT_ERR(__curfile_update_check(cbt));
 
-		if (cbt->compare != 0 || !__wt_cursor_valid(cbt, NULL))
+		if (cbt->compare != 0)
+			WT_ERR(WT_NOTFOUND);
+		WT_ERR(__wt_cursor_valid(cbt, NULL, &valid));
+		if (!valid)
 			WT_ERR(WT_NOTFOUND);
 
 		ret = __cursor_row_modify(session, cbt, WT_UPDATE_TOMBSTONE);
@@ -1043,7 +1056,10 @@ retry:	if (positioned == POSITIONED)
 		WT_ERR(__curfile_update_check(cbt));
 
 		/* Remove the record if it exists. */
-		if (cbt->compare != 0 || !__wt_cursor_valid(cbt, NULL)) {
+		valid = false;
+		if (cbt->compare == 0)
+			WT_ERR(__wt_cursor_valid(cbt, NULL, &valid));
+		if (cbt->compare != 0 || !valid) {
 			if (!__cursor_fix_implicit(btree, cbt))
 				WT_ERR(WT_NOTFOUND);
 			/*
@@ -1143,6 +1159,7 @@ __btcur_update(WT_CURSOR_BTREE *cbt, WT_ITEM *value, u_int modify_type)
 	WT_CURSOR *cursor;
 	WT_DECL_RET;
 	WT_SESSION_IMPL *session;
+	bool valid;
 
 	btree = cbt->btree;
 	cursor = &cbt->iface;
@@ -1207,7 +1224,10 @@ retry:	WT_ERR(__cursor_func_init(cbt, true));
 		 */
 		if (!F_ISSET(cursor, WT_CURSTD_OVERWRITE)) {
 			WT_ERR(__curfile_update_check(cbt));
-			if (cbt->compare != 0 || !__wt_cursor_valid(cbt, NULL))
+			if (cbt->compare != 0)
+				WT_ERR(WT_NOTFOUND);
+			WT_ERR(__wt_cursor_valid(cbt, NULL, &valid));
+			if (!valid)
 				WT_ERR(WT_NOTFOUND);
 		}
 		ret = __cursor_row_modify_v(session, cbt, value, modify_type);
@@ -1224,8 +1244,10 @@ retry:	WT_ERR(__cursor_func_init(cbt, true));
 		 */
 		if (!F_ISSET(cursor, WT_CURSTD_OVERWRITE)) {
 			WT_ERR(__curfile_update_check(cbt));
-			if ((cbt->compare != 0 ||
-			    !__wt_cursor_valid(cbt, NULL)) &&
+			valid = false;
+			if (cbt->compare == 0)
+				WT_ERR(__wt_cursor_valid(cbt, NULL, &valid));
+			if ((cbt->compare != 0 || !valid) &&
 			    !__cursor_fix_implicit(btree, cbt))
 				WT_ERR(WT_NOTFOUND);
 		}
diff --git a/src/third_party/wiredtiger/src/btree/bt_random.c b/src/third_party/wiredtiger/src/btree/bt_random.c
index 03b5039b00b..8eb120f06ec 100644
--- a/src/third_party/wiredtiger/src/btree/bt_random.c
+++ b/src/third_party/wiredtiger/src/btree/bt_random.c
@@ -302,6 +302,7 @@ __wt_btcur_next_random(WT_CURSOR_BTREE *cbt)
 	WT_UPDATE *upd;
 	wt_off_t size;
 	uint64_t n, skip;
+	bool valid;
 
 	btree = cbt->btree;
 	cursor = &cbt->iface;
@@ -421,7 +422,8 @@ random_page_entry:
 	 * the next entry, if that doesn't work, move to the previous entry.
 	 */
 	WT_ERR(__wt_row_random_leaf(session, cbt));
-	if (__wt_cursor_valid(cbt, &upd)) {
+	WT_ERR(__wt_cursor_valid(cbt, &upd, &valid));
+	if (valid) {
 		WT_ERR(__wt_key_return(session, cbt));
 		WT_ERR(__wt_value_return(session, cbt, upd));
 	} else {
diff --git a/src/third_party/wiredtiger/src/config/config_def.c b/src/third_party/wiredtiger/src/config/config_def.c
index f473cfe3e8d..ffcb2139330 100644
--- a/src/third_party/wiredtiger/src/config/config_def.c
+++ b/src/third_party/wiredtiger/src/config/config_def.c
@@ -46,8 +46,8 @@ static const WT_CONFIG_CHECK confchk_WT_CONNECTION_open_session[] = {
 
 static const WT_CONFIG_CHECK confchk_WT_CONNECTION_query_timestamp[] = {
 	{ "get", "string",
-	    NULL, "choices=[\"all_committed\",\"oldest\",\"pinned\","
-	    "\"recovery\",\"stable\"]",
+	    NULL, "choices=[\"all_committed\",\"last_checkpoint\",\"oldest\""
+	    ",\"pinned\",\"recovery\",\"stable\"]",
 	    NULL, 0 },
 	{ NULL, NULL, NULL, NULL, NULL, 0 }
 };
diff --git a/src/third_party/wiredtiger/src/include/api.h b/src/third_party/wiredtiger/src/include/api.h
index afefbe8ad5c..ff757c4bfb5 100644
--- a/src/third_party/wiredtiger/src/include/api.h
+++ b/src/third_party/wiredtiger/src/include/api.h
@@ -68,6 +68,7 @@
 		if ((ret) != 0 &&					\
 		    (ret) != WT_NOTFOUND &&				\
 		    (ret) != WT_DUPLICATE_KEY &&			\
+		    (ret) != WT_PREPARE_CONFLICT &&			\
 		    F_ISSET(&(s)->txn, WT_TXN_RUNNING))			\
 			F_SET(&(s)->txn, WT_TXN_ERROR);			\
 		/*							\
@@ -237,6 +238,7 @@
 	JOINABLE_CURSOR_CALL_CHECK(cur)
 
 #define	CURSOR_UPDATE_API_END(s, ret)					\
+	((ret == WT_PREPARE_CONFLICT) ? (ret = WT_ROLLBACK) : ret );	\
 	TXN_API_END(s, ret)
 
 #define	ASYNCOP_API_CALL(conn, s, n)					\
diff --git a/src/third_party/wiredtiger/src/include/btmem.h b/src/third_party/wiredtiger/src/include/btmem.h
index 7ba73d1b94f..d56a3773933 100644
--- a/src/third_party/wiredtiger/src/include/btmem.h
+++ b/src/third_party/wiredtiger/src/include/btmem.h
@@ -997,7 +997,7 @@ struct __wt_update {
 						   finalized prepare */
 #define	WT_UPDATE_STATE_LOCKED		1	/* locked */
 #define	WT_UPDATE_STATE_PREPARED	2	/* prepared */
-	uint8_t state;			/* state (one byte : conserve memory) */
+	volatile uint8_t state;
 
 	/* If the update includes a complete value. */
 #define	WT_UPDATE_DATA_VALUE(upd)					\
diff --git a/src/third_party/wiredtiger/src/include/cursor.h b/src/third_party/wiredtiger/src/include/cursor.h
index 70f9318f6d7..ec5c6689c3f 100644
--- a/src/third_party/wiredtiger/src/include/cursor.h
+++ b/src/third_party/wiredtiger/src/include/cursor.h
@@ -217,20 +217,23 @@ struct __wt_cursor_btree {
 #endif
 
 /* AUTOMATIC FLAG VALUE GENERATION START */
-#define	WT_CBT_ACTIVE		0x01u	/* Active in the tree */
-#define	WT_CBT_ITERATE_APPEND	0x02u	/* Col-store: iterating append list */
-#define	WT_CBT_ITERATE_NEXT	0x04u	/* Next iteration configuration */
-#define	WT_CBT_ITERATE_PREV	0x08u	/* Prev iteration configuration */
-#define	WT_CBT_NO_TXN   	0x10u	/* Non-txn cursor (e.g. a checkpoint) */
-#define	WT_CBT_SEARCH_SMALLEST	0x20u	/* Row-store: small-key insert list */
-#define	WT_CBT_VAR_ONPAGE_MATCH	0x40u	/* Var-store: on-page recno match */
+#define	WT_CBT_ACTIVE		0x001u	/* Active in the tree */
+#define	WT_CBT_ITERATE_APPEND	0x002u	/* Col-store: iterating append list */
+#define	WT_CBT_ITERATE_NEXT	0x004u	/* Next iteration configuration */
+#define	WT_CBT_ITERATE_PREV	0x008u	/* Prev iteration configuration */
+#define	WT_CBT_NO_TXN   	0x010u	/* Non-txn cursor (e.g. a checkpoint) */
+#define	WT_CBT_RETRY_NEXT	0x020u	/* Next, resulted in prepare conflict */
+#define	WT_CBT_RETRY_PREV	0x040u	/* Prev, resulted in prepare conflict */
+#define	WT_CBT_SEARCH_SMALLEST	0x080u	/* Row-store: small-key insert list */
+#define	WT_CBT_VAR_ONPAGE_MATCH	0x100u	/* Var-store: on-page recno match */
 /* AUTOMATIC FLAG VALUE GENERATION STOP */
 
 #define	WT_CBT_POSITION_MASK		/* Flags associated with position */ \
 	(WT_CBT_ITERATE_APPEND | WT_CBT_ITERATE_NEXT | WT_CBT_ITERATE_PREV | \
-	WT_CBT_SEARCH_SMALLEST | WT_CBT_VAR_ONPAGE_MATCH)
+	WT_CBT_RETRY_NEXT | WT_CBT_RETRY_PREV | WT_CBT_SEARCH_SMALLEST |     \
+	WT_CBT_VAR_ONPAGE_MATCH)
 
-	uint8_t flags;
+	uint32_t flags;
 };
 
 struct __wt_cursor_bulk {
diff --git a/src/third_party/wiredtiger/src/include/cursor.i b/src/third_party/wiredtiger/src/include/cursor.i
index a4e986c4325..d338c47dfae 100644
--- a/src/third_party/wiredtiger/src/include/cursor.i
+++ b/src/third_party/wiredtiger/src/include/cursor.i
@@ -311,6 +311,20 @@ __wt_cursor_dhandle_decr_use(WT_SESSION_IMPL *session)
 }
 
 /*
+ * __cursor_kv_return --
+ *      Return a page referenced key/value pair to the application.
+ */
+static inline int
+__cursor_kv_return(
+    WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt, WT_UPDATE *upd)
+{
+	WT_RET(__wt_key_return(session, cbt));
+	WT_RET(__wt_value_return(session, cbt, upd));
+
+	return (0);
+}
+
+/*
  * __cursor_func_init --
  *	Cursor call setup.
  */
diff --git a/src/third_party/wiredtiger/src/include/extern.h b/src/third_party/wiredtiger/src/include/extern.h
index 8b69f9ef244..508480b95c2 100644
--- a/src/third_party/wiredtiger/src/include/extern.h
+++ b/src/third_party/wiredtiger/src/include/extern.h
@@ -100,7 +100,7 @@ extern void __wt_cursor_key_order_reset(WT_CURSOR_BTREE *cbt);
 extern void __wt_btcur_iterate_setup(WT_CURSOR_BTREE *cbt);
 extern int __wt_btcur_next(WT_CURSOR_BTREE *cbt, bool truncating) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_btcur_prev(WT_CURSOR_BTREE *cbt, bool truncating) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
-extern bool __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp);
+extern int __wt_cursor_valid(WT_CURSOR_BTREE *cbt, WT_UPDATE **updp, bool *valid) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_btcur_reset(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_btcur_search(WT_CURSOR_BTREE *cbt) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_btcur_search_near(WT_CURSOR_BTREE *cbt, int *exactp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
diff --git a/src/third_party/wiredtiger/src/include/mutex.h b/src/third_party/wiredtiger/src/include/mutex.h
index 2a3fc7448f8..ba32d166f03 100644
--- a/src/third_party/wiredtiger/src/include/mutex.h
+++ b/src/third_party/wiredtiger/src/include/mutex.h
@@ -44,9 +44,8 @@ struct __wt_rwlock {			/* Read/write lock */
 			uint8_t current;	/* Current ticket */
 			uint8_t next;		/* Next available ticket */
 			uint8_t reader;		/* Read queue ticket */
-			uint8_t __notused;	/* Padding */
-			uint16_t readers_active;/* Count of active readers */
-			uint16_t readers_queued;/* Count of queued readers */
+			uint8_t readers_queued; /* Count of queued readers */
+			uint32_t readers_active;/* Count of active readers */
 		} s;
 	} u;
 
diff --git a/src/third_party/wiredtiger/src/include/stat.h b/src/third_party/wiredtiger/src/include/stat.h
index 7ef63cb0eaf..01a982b8602 100644
--- a/src/third_party/wiredtiger/src/include/stat.h
+++ b/src/third_party/wiredtiger/src/include/stat.h
@@ -627,6 +627,9 @@ struct __wt_connection_stats {
 	int64_t txn_read_queue_head;
 	int64_t txn_read_queue_inserts;
 	int64_t txn_read_queue_len;
+	int64_t txn_rollback_to_stable;
+	int64_t txn_rollback_upd_aborted;
+	int64_t txn_rollback_las_removed;
 	int64_t txn_set_ts;
 	int64_t txn_set_ts_commit;
 	int64_t txn_set_ts_commit_upd;
diff --git a/src/third_party/wiredtiger/src/include/txn.h b/src/third_party/wiredtiger/src/include/txn.h
index dd7f5d4a8bc..19e0be2d695 100644
--- a/src/third_party/wiredtiger/src/include/txn.h
+++ b/src/third_party/wiredtiger/src/include/txn.h
@@ -102,6 +102,7 @@ struct __wt_txn_global {
 	volatile uint64_t oldest_id;
 
 	WT_DECL_TIMESTAMP(commit_timestamp)
+	WT_DECL_TIMESTAMP(last_ckpt_timestamp)
 	WT_DECL_TIMESTAMP(oldest_timestamp)
 	WT_DECL_TIMESTAMP(pinned_timestamp)
 	WT_DECL_TIMESTAMP(recovery_timestamp)
diff --git a/src/third_party/wiredtiger/src/include/txn.i b/src/third_party/wiredtiger/src/include/txn.i
index 5fcf8ee11c9..36cac1a26f3 100644
--- a/src/third_party/wiredtiger/src/include/txn.i
+++ b/src/third_party/wiredtiger/src/include/txn.i
@@ -9,6 +9,11 @@
 static inline int __wt_txn_id_check(WT_SESSION_IMPL *session);
 static inline void __wt_txn_read_last(WT_SESSION_IMPL *session);
 
+typedef enum {
+	WT_VISIBLE_FALSE=0,     /* Not a visible update */
+	WT_VISIBLE_PREPARE=1,   /* Prepared update */
+	WT_VISIBLE_TRUE=2       /* A visible update */
+} WT_VISIBLE_TYPE;
 #ifdef HAVE_TIMESTAMPS
 /*
  * __wt_txn_timestamp_flags --
@@ -539,33 +544,74 @@ __wt_txn_visible(
 }
 
 /*
+ * __wt_txn_upd_visible_type --
+ *      Visible type of given update for the current transaction.
+ */
+static inline WT_VISIBLE_TYPE
+__wt_txn_upd_visible_type(WT_SESSION_IMPL *session, WT_UPDATE *upd)
+{
+	uint8_t upd_state;
+	bool upd_visible;
+
+	for (;;__wt_yield()) {
+		/* Commit is in progress, yield and try again. */
+		if ((upd_state = upd->state) == WT_UPDATE_STATE_LOCKED)
+			continue;
+
+		upd_visible = __wt_txn_visible(
+		    session, upd->txnid, WT_TIMESTAMP_NULL(&upd->timestamp));
+
+		/*
+		 * The visibility check is only valid if the update does not
+		 * change state.  If the state does change, recheck visibility.
+		 */
+		if (upd->state == upd_state)
+			break;
+	}
+
+	if (!upd_visible)
+		return (WT_VISIBLE_FALSE);
+
+	if (upd_state == WT_UPDATE_STATE_PREPARED)
+		return (F_ISSET(&session->txn, WT_TXN_IGNORE_PREPARE) ?
+		    WT_VISIBLE_FALSE : WT_VISIBLE_PREPARE);
+
+	return (WT_VISIBLE_TRUE);
+}
+
+/*
  * __wt_txn_upd_visible --
  *	Can the current transaction see the given update.
  */
 static inline bool
 __wt_txn_upd_visible(WT_SESSION_IMPL *session, WT_UPDATE *upd)
 {
-	return (__wt_txn_visible(session,
-	    upd->txnid, WT_TIMESTAMP_NULL(&upd->timestamp)));
+	return (__wt_txn_upd_visible_type(session, upd) == WT_VISIBLE_TRUE);
 }
 
 /*
  * __wt_txn_read --
  *	Get the first visible update in a list (or NULL if none are visible).
  */
-static inline WT_UPDATE *
-__wt_txn_read(WT_SESSION_IMPL *session, WT_UPDATE *upd)
+static inline int
+__wt_txn_read(WT_SESSION_IMPL *session, WT_UPDATE *upd, WT_UPDATE **updp)
 {
 	static WT_UPDATE tombstone = {
 		.txnid = WT_TXN_NONE, .type = WT_UPDATE_TOMBSTONE
 	};
+	WT_VISIBLE_TYPE upd_visible;
 	bool skipped_birthmark;
 
+	*updp = NULL;
 	for (skipped_birthmark = false; upd != NULL; upd = upd->next) {
 		/* Skip reserved place-holders, they're never visible. */
-		if (upd->type != WT_UPDATE_RESERVE &&
-		    __wt_txn_upd_visible(session, upd))
-			break;
+		if (upd->type != WT_UPDATE_RESERVE) {
+			upd_visible = __wt_txn_upd_visible_type(session, upd);
+			if (upd_visible == WT_VISIBLE_TRUE)
+				break;
+			if (upd_visible == WT_VISIBLE_PREPARE)
+				return (WT_PREPARE_CONFLICT);
+		}
 		/* An invisible birthmark is equivalent to a tombstone. */
 		if (upd->type == WT_UPDATE_BIRTHMARK)
 			skipped_birthmark = true;
@@ -574,7 +620,8 @@ __wt_txn_read(WT_SESSION_IMPL *session, WT_UPDATE *upd)
 	if (upd == NULL && skipped_birthmark)
 		upd = &tombstone;
 
-	return (upd == NULL || upd->type == WT_UPDATE_BIRTHMARK ? NULL : upd);
+	*updp = (upd == NULL || upd->type == WT_UPDATE_BIRTHMARK ? NULL : upd);
+	return (0);
 }
 
 /*
@@ -786,21 +833,32 @@ static inline int
 __wt_txn_update_check(WT_SESSION_IMPL *session, WT_UPDATE *upd)
 {
 	WT_TXN *txn;
+	bool ignore_prepare_set;
 
 	txn = &session->txn;
-	if (txn->isolation == WT_ISO_SNAPSHOT)
-		while (upd != NULL && !__wt_txn_upd_visible(session, upd)) {
-			if (upd->txnid != WT_TXN_ABORTED) {
-				WT_STAT_CONN_INCR(
-				    session, txn_update_conflict);
-				WT_STAT_DATA_INCR(
-				    session, txn_update_conflict);
-				return (__wt_txn_rollback_required(session,
+	if (txn->isolation != WT_ISO_SNAPSHOT)
+		return (0);
+
+	/*
+	 * Clear the ignore prepare setting of txn, as it is not supposed, to
+	 * affect the visibility for update operations.
+	 */
+	ignore_prepare_set = F_ISSET(txn, WT_TXN_IGNORE_PREPARE);
+	F_CLR(txn, WT_TXN_IGNORE_PREPARE);
+	for (;upd != NULL && !__wt_txn_upd_visible(session, upd);
+	    upd = upd->next) {
+		if (upd->txnid != WT_TXN_ABORTED) {
+			if (ignore_prepare_set)
+				F_SET(txn, WT_TXN_IGNORE_PREPARE);
+			WT_STAT_CONN_INCR(session, txn_update_conflict);
+			WT_STAT_DATA_INCR(session, txn_update_conflict);
+			return (__wt_txn_rollback_required(session,
 				    "conflict between concurrent operations"));
-			}
-			upd = upd->next;
 		}
+	}
 
+	if (ignore_prepare_set)
+		F_SET(txn, WT_TXN_IGNORE_PREPARE);
 	return (0);
 }
 
diff --git a/src/third_party/wiredtiger/src/include/wiredtiger.in b/src/third_party/wiredtiger/src/include/wiredtiger.in
index a75c22497ce..1f2a438b8e9 100644
--- a/src/third_party/wiredtiger/src/include/wiredtiger.in
+++ b/src/third_party/wiredtiger/src/include/wiredtiger.in
@@ -2431,8 +2431,9 @@ struct __wt_connection {
 	 * timestamps of all active readers\, and \c stable returns the most
 	 * recent \c stable_timestamp set with WT_CONNECTION::set_timestamp.
 	 * See @ref transaction_timestamps., a string\, chosen from the
-	 * following options: \c "all_committed"\, \c "oldest"\, \c "pinned"\,
-	 * \c "recovery"\, \c "stable"; default \c all_committed.}
+	 * following options: \c "all_committed"\, \c "last_checkpoint"\, \c
+	 * "oldest"\, \c "pinned"\, \c "recovery"\, \c "stable"; default \c
+	 * all_committed.}
 	 * @configend
 	 * @errors
 	 * If there is no matching timestamp (e.g., if this method is called
@@ -5562,81 +5563,87 @@ extern int wiredtiger_extension_terminate(WT_CONNECTION *connection);
 #define	WT_STAT_CONN_TXN_READ_QUEUE_INSERTS		1312
 /*! transaction: read timestamp queue length */
 #define	WT_STAT_CONN_TXN_READ_QUEUE_LEN			1313
+/*! transaction: rollback to stable calls */
+#define	WT_STAT_CONN_TXN_ROLLBACK_TO_STABLE		1314
+/*! transaction: rollback to stable updates aborted */
+#define	WT_STAT_CONN_TXN_ROLLBACK_UPD_ABORTED		1315
+/*! transaction: rollback to stable updates removed from lookaside */
+#define	WT_STAT_CONN_TXN_ROLLBACK_LAS_REMOVED		1316
 /*! transaction: set timestamp calls */
-#define	WT_STAT_CONN_TXN_SET_TS				1314
+#define	WT_STAT_CONN_TXN_SET_TS				1317
 /*! transaction: set timestamp commit calls */
-#define	WT_STAT_CONN_TXN_SET_TS_COMMIT			1315
+#define	WT_STAT_CONN_TXN_SET_TS_COMMIT			1318
 /*! transaction: set timestamp commit updates */
-#define	WT_STAT_CONN_TXN_SET_TS_COMMIT_UPD		1316
+#define	WT_STAT_CONN_TXN_SET_TS_COMMIT_UPD		1319
 /*! transaction: set timestamp oldest calls */
-#define	WT_STAT_CONN_TXN_SET_TS_OLDEST			1317
+#define	WT_STAT_CONN_TXN_SET_TS_OLDEST			1320
 /*! transaction: set timestamp oldest updates */
-#define	WT_STAT_CONN_TXN_SET_TS_OLDEST_UPD		1318
+#define	WT_STAT_CONN_TXN_SET_TS_OLDEST_UPD		1321
 /*! transaction: set timestamp stable calls */
-#define	WT_STAT_CONN_TXN_SET_TS_STABLE			1319
+#define	WT_STAT_CONN_TXN_SET_TS_STABLE			1322
 /*! transaction: set timestamp stable updates */
-#define	WT_STAT_CONN_TXN_SET_TS_STABLE_UPD		1320
+#define	WT_STAT_CONN_TXN_SET_TS_STABLE_UPD		1323
 /*! transaction: transaction begins */
-#define	WT_STAT_CONN_TXN_BEGIN				1321
+#define	WT_STAT_CONN_TXN_BEGIN				1324
 /*! transaction: transaction checkpoint currently running */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1322
+#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1325
 /*! transaction: transaction checkpoint generation */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1323
+#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1326
 /*! transaction: transaction checkpoint max time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1324
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1327
 /*! transaction: transaction checkpoint min time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1325
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1328
 /*! transaction: transaction checkpoint most recent time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1326
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1329
 /*! transaction: transaction checkpoint scrub dirty target */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1327
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1330
 /*! transaction: transaction checkpoint scrub time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1328
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1331
 /*! transaction: transaction checkpoint total time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1329
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1332
 /*! transaction: transaction checkpoints */
-#define	WT_STAT_CONN_TXN_CHECKPOINT			1330
+#define	WT_STAT_CONN_TXN_CHECKPOINT			1333
 /*!
  * transaction: transaction checkpoints skipped because database was
  * clean
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SKIPPED		1331
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SKIPPED		1334
 /*! transaction: transaction failures due to cache overflow */
-#define	WT_STAT_CONN_TXN_FAIL_CACHE			1332
+#define	WT_STAT_CONN_TXN_FAIL_CACHE			1335
 /*!
  * transaction: transaction fsync calls for checkpoint after allocating
  * the transaction ID
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1333
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1336
 /*!
  * transaction: transaction fsync duration for checkpoint after
  * allocating the transaction ID (usecs)
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1334
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1337
 /*! transaction: transaction range of IDs currently pinned */
-#define	WT_STAT_CONN_TXN_PINNED_RANGE			1335
+#define	WT_STAT_CONN_TXN_PINNED_RANGE			1338
 /*! transaction: transaction range of IDs currently pinned by a checkpoint */
-#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1336
+#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1339
 /*!
  * transaction: transaction range of IDs currently pinned by named
  * snapshots
  */
-#define	WT_STAT_CONN_TXN_PINNED_SNAPSHOT_RANGE		1337
+#define	WT_STAT_CONN_TXN_PINNED_SNAPSHOT_RANGE		1340
 /*! transaction: transaction range of timestamps currently pinned */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP		1338
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP		1341
 /*!
  * transaction: transaction range of timestamps pinned by the oldest
  * timestamp
  */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_OLDEST	1339
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_OLDEST	1342
 /*! transaction: transaction sync calls */
-#define	WT_STAT_CONN_TXN_SYNC				1340
+#define	WT_STAT_CONN_TXN_SYNC				1343
 /*! transaction: transactions committed */
-#define	WT_STAT_CONN_TXN_COMMIT				1341
+#define	WT_STAT_CONN_TXN_COMMIT				1344
 /*! transaction: transactions rolled back */
-#define	WT_STAT_CONN_TXN_ROLLBACK			1342
+#define	WT_STAT_CONN_TXN_ROLLBACK			1345
 /*! transaction: update conflicts */
-#define	WT_STAT_CONN_TXN_UPDATE_CONFLICT		1343
+#define	WT_STAT_CONN_TXN_UPDATE_CONFLICT		1346
 
 /*!
  * @}
diff --git a/src/third_party/wiredtiger/src/reconcile/rec_write.c b/src/third_party/wiredtiger/src/reconcile/rec_write.c
index f4d0fc0b1ef..a2ce2c136b5 100644
--- a/src/third_party/wiredtiger/src/reconcile/rec_write.c
+++ b/src/third_party/wiredtiger/src/reconcile/rec_write.c
@@ -1341,12 +1341,14 @@ __rec_txn_read(WT_SESSION_IMPL *session, WT_RECONCILE *r,
 		 * started.  The global commit point can move forward during
 		 * reconciliation so we use a cached copy to avoid races when a
 		 * concurrent transaction commits or rolls back while we are
-		 * examining its updates.
+		 * examining its updates. As prepared transaction id's are
+		 * globally visible, need to check the update state as well.
 		 */
 		if (F_ISSET(r, WT_REC_EVICT) &&
+		    (upd->state != WT_UPDATE_STATE_READY ||
 		    (F_ISSET(r, WT_REC_VISIBLE_ALL) ?
 		    WT_TXNID_LE(r->last_running, txnid) :
-		    !__txn_visible_id(session, txnid))) {
+		    !__txn_visible_id(session, txnid)))) {
 			uncommitted = r->update_uncommitted = true;
 			continue;
 		}
diff --git a/src/third_party/wiredtiger/src/support/mtx_rw.c b/src/third_party/wiredtiger/src/support/mtx_rw.c
index 572592b9fbc..b554f589b3d 100644
--- a/src/third_party/wiredtiger/src/support/mtx_rw.c
+++ b/src/third_party/wiredtiger/src/support/mtx_rw.c
@@ -48,9 +48,8 @@
  *		uint8_t current;		// Current ticket
  *		uint8_t next;			// Next available ticket
  *		uint8_t reader;			// Read queue ticket
- *		uint8_t __notused;		// Padding
- *		uint16_t readers_active;	// Count of active readers
- *		uint16_t readers_queued;	// Count of queued readers
+ *		uint8_t readers_queued;		// Count of queued readers
+ *		uint32_t readers_active;	// Count of active readers
  *	} s;
  * } u;
  *
@@ -75,6 +74,12 @@
  * 'reader' to 'next' (i.e. readers are scheduled after any queued writers,
  * avoiding starvation), then atomically incrementing 'readers_queued'.
  *
+ * We limit how many readers can queue: we don't allow more readers to queue
+ * than there are active writers (calculated as `next - current`): otherwise,
+ * in write-heavy workloads, readers can keep queuing up in front of writers
+ * and throughput is unstable.  The remaining read requests wait without any
+ * ordering.
+ *
  * The 'next' field is a 1-byte value so the available ticket number wraps
  * after 256 requests. If a thread's write lock request would cause the 'next'
  * field to catch up with 'current', instead it waits to avoid the same ticket
diff --git a/src/third_party/wiredtiger/src/support/stat.c b/src/third_party/wiredtiger/src/support/stat.c
index 40a07be0174..ae13f7d8abe 100644
--- a/src/third_party/wiredtiger/src/support/stat.c
+++ b/src/third_party/wiredtiger/src/support/stat.c
@@ -1052,6 +1052,9 @@ static const char * const __stats_connection_desc[] = {
 	"transaction: read timestamp queue inserts to head",
 	"transaction: read timestamp queue inserts total",
 	"transaction: read timestamp queue length",
+	"transaction: rollback to stable calls",
+	"transaction: rollback to stable updates aborted",
+	"transaction: rollback to stable updates removed from lookaside",
 	"transaction: set timestamp calls",
 	"transaction: set timestamp commit calls",
 	"transaction: set timestamp commit updates",
@@ -1438,6 +1441,9 @@ __wt_stat_connection_clear_single(WT_CONNECTION_STATS *stats)
 	stats->txn_read_queue_head = 0;
 	stats->txn_read_queue_inserts = 0;
 	stats->txn_read_queue_len = 0;
+	stats->txn_rollback_to_stable = 0;
+	stats->txn_rollback_upd_aborted = 0;
+	stats->txn_rollback_las_removed = 0;
 	stats->txn_set_ts = 0;
 	stats->txn_set_ts_commit = 0;
 	stats->txn_set_ts_commit_upd = 0;
@@ -1956,6 +1962,12 @@ __wt_stat_connection_aggregate(
 	to->txn_read_queue_inserts +=
 	    WT_STAT_READ(from, txn_read_queue_inserts);
 	to->txn_read_queue_len += WT_STAT_READ(from, txn_read_queue_len);
+	to->txn_rollback_to_stable +=
+	    WT_STAT_READ(from, txn_rollback_to_stable);
+	to->txn_rollback_upd_aborted +=
+	    WT_STAT_READ(from, txn_rollback_upd_aborted);
+	to->txn_rollback_las_removed +=
+	    WT_STAT_READ(from, txn_rollback_las_removed);
 	to->txn_set_ts += WT_STAT_READ(from, txn_set_ts);
 	to->txn_set_ts_commit += WT_STAT_READ(from, txn_set_ts_commit);
 	to->txn_set_ts_commit_upd +=
diff --git a/src/third_party/wiredtiger/src/txn/txn_ckpt.c b/src/third_party/wiredtiger/src/txn/txn_ckpt.c
index 1235bc8c2b2..d3f11c5fa69 100644
--- a/src/third_party/wiredtiger/src/txn/txn_ckpt.c
+++ b/src/third_party/wiredtiger/src/txn/txn_ckpt.c
@@ -748,6 +748,7 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	WT_CACHE *cache;
 	WT_CONNECTION_IMPL *conn;
 	WT_DECL_RET;
+	WT_DECL_TIMESTAMP(ckpt_tmp_ts)
 	WT_TXN *txn;
 	WT_TXN_GLOBAL *txn_global;
 	WT_TXN_ISOLATION saved_isolation;
@@ -899,6 +900,15 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	 * checkpointing the metadata since we know that all files in the
 	 * checkpoint are now in a consistent state.
 	 */
+#ifdef HAVE_TIMESTAMPS
+	/*
+	 * Record the timestamp from the transaction if we were successful.
+	 * Store it in a temp variable now because it will be invalidated during
+	 * commit but we don't want to set it until we know the checkpoint
+	 * is successful.
+	 */
+	__wt_timestamp_set(&ckpt_tmp_ts, &txn->read_timestamp);
+#endif
 	WT_ERR(__wt_txn_commit(session, NULL));
 
 	/*
@@ -942,8 +952,13 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	 */
 	txn_global->checkpoint_state.pinned_id = WT_TXN_NONE;
 
-	if (full)
+	if (full) {
 		__checkpoint_stats(session);
+#ifdef HAVE_TIMESTAMPS
+		__wt_timestamp_set(
+		    &conn->txn_global.last_ckpt_timestamp, &ckpt_tmp_ts);
+#endif
+	}
 
 err:	/*
 	 * Reset the timer so that next checkpoint tracks the progress only if
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 d31b3995092..eef2fde5284 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
@@ -74,6 +74,7 @@ __txn_rollback_to_stable_lookaside_fixup(WT_SESSION_IMPL *session)
 		    &rollback_timestamp, las_timestamp.data) < 0) {
 			WT_ERR(cursor->remove(cursor));
 			++remove_cnt;
+			WT_STAT_CONN_INCR(session, txn_rollback_las_removed);
 		} else
 			++las_total;
 	}
@@ -111,6 +112,7 @@ __txn_abort_newer_update(WT_SESSION_IMPL *session,
 		if (__wt_timestamp_cmp(
 		    rollback_timestamp, &next_upd->timestamp) < 0) {
 			next_upd->txnid = WT_TXN_ABORTED;
+			WT_STAT_CONN_INCR(session, txn_rollback_upd_aborted);
 			__wt_timestamp_set_zero(&next_upd->timestamp);
 
 			/*
@@ -425,6 +427,7 @@ __wt_txn_rollback_to_stable(WT_SESSION_IMPL *session, const char *cfg[])
 
 	conn = S2C(session);
 
+	WT_STAT_CONN_INCR(session, txn_rollback_to_stable);
 	/*
 	 * Mark that a rollback operation is in progress and wait for eviction
 	 * to drain.  This is necessary because lookaside eviction uses
diff --git a/src/third_party/wiredtiger/src/txn/txn_timestamp.c b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
index 280425eb56e..2266a9cd6f5 100644
--- a/src/third_party/wiredtiger/src/txn/txn_timestamp.c
+++ b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
@@ -239,7 +239,10 @@ __txn_global_query_timestamp(
 			break;
 		}
 		__wt_readunlock(session, &txn_global->commit_timestamp_rwlock);
-	} else if (WT_STRING_MATCH("oldest", cval.str, cval.len)) {
+	} else if (WT_STRING_MATCH("last_checkpoint", cval.str, cval.len))
+		/* Read-only value forever. No lock needed. */
+		__wt_timestamp_set(&ts, &txn_global->last_ckpt_timestamp);
+	else if (WT_STRING_MATCH("oldest", cval.str, cval.len)) {
 		if (!txn_global->has_oldest_timestamp)
 			return (WT_NOTFOUND);
 		WT_WITH_TIMESTAMP_READLOCK(session, &txn_global->rwlock,
diff --git a/src/third_party/wiredtiger/test/csuite/rwlock/main.c b/src/third_party/wiredtiger/test/csuite/rwlock/main.c
index e1d00344ee2..f69628dca40 100644
--- a/src/third_party/wiredtiger/test/csuite/rwlock/main.c
+++ b/src/third_party/wiredtiger/test/csuite/rwlock/main.c
@@ -171,8 +171,8 @@ thread_dump(void *arg) {
 		sleep(1);
 		printf("\n"
 		    "rwlock { current %" PRIu8 ", next %" PRIu8
-		    ", reader %" PRIu8 ", readers_active %" PRIu16
-		    ", readers_queued %" PRIu16 " }\n",
+		    ", reader %" PRIu8 ", readers_active %" PRIu32
+		    ", readers_queued %" PRIu8 " }\n",
 		    rwlock.u.s.current,
 		    rwlock.u.s.next,
 		    rwlock.u.s.reader,
diff --git a/src/third_party/wiredtiger/test/format/config.c b/src/third_party/wiredtiger/test/format/config.c
index 8d85d331c89..d46b0868887 100644
--- a/src/third_party/wiredtiger/test/format/config.c
+++ b/src/third_party/wiredtiger/test/format/config.c
@@ -191,9 +191,13 @@ config_setup(void)
 	/*
 	 * Turn off truncate for LSM runs (some configurations with truncate
 	 * always results in a timeout).
+	 *
+	 * WiredTiger doesn't currently support truncate and prepare at the
+	 * same time, see WT-3922. For now, pick one on each run.
 	 */
-	if (!config_is_perm("truncate") && DATASOURCE("lsm"))
-		config_single("truncate=off", 0);
+	if (!config_is_perm("truncate"))
+		if (DATASOURCE("lsm") || mmrand(NULL, 0, 1) == 1)
+			config_single("truncate=off", 0);
 
 	/* Give Helium configuration a final review. */
 	if (DATASOURCE("helium"))
diff --git a/src/third_party/wiredtiger/test/format/ops.c b/src/third_party/wiredtiger/test/format/ops.c
index 4c54972516e..2466fe4d64d 100644
--- a/src/third_party/wiredtiger/test/format/ops.c
+++ b/src/third_party/wiredtiger/test/format/ops.c
@@ -403,10 +403,8 @@ snap_check(WT_CURSOR *cursor,
 			break;
 		case WT_NOTFOUND:
 			break;
-		case WT_ROLLBACK:
-			return (WT_ROLLBACK);
 		default:
-			testutil_die(ret, "WT_CURSOR.search");
+			return (ret);
 		}
 
 		/* Check for simple matches. */
@@ -644,6 +642,19 @@ prepare_transaction(TINFO *tinfo, WT_SESSION *session)
 }
 
 /*
+ * OP_FAILED --
+ *	General error handling.
+ */
+#define	OP_FAILED(notfound_ok) do {					\
+	positioned = false;						\
+	if (intxn && (ret == WT_CACHE_FULL || ret == WT_ROLLBACK))	\
+		goto deadlock;						\
+	testutil_assert((notfound_ok && ret == WT_NOTFOUND) ||		\
+	    ret == WT_CACHE_FULL ||					\
+	    ret == WT_PREPARE_CONFLICT || ret == WT_ROLLBACK);		\
+} while (0)
+
+/*
  * ops --
  *     Per-thread operations.
  */
@@ -825,11 +836,8 @@ ops(void *arg)
 			if (ret == 0) {
 				positioned = true;
 				SNAP_TRACK(READ, tinfo);
-			} else {
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(ret == WT_NOTFOUND);
-			}
+			} else
+				OP_FAILED(true);
 		}
 
 		/* Optionally reserve a row. */
@@ -847,12 +855,8 @@ ops(void *arg)
 				positioned = true;
 
 				__wt_yield();	/* Let other threads proceed. */
-			} else {
-				positioned = false;
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(ret == WT_NOTFOUND);
-			}
+			} else
+				OP_FAILED(true);
 		}
 
 		/* Perform the operation. */
@@ -881,11 +885,8 @@ ops(void *arg)
 			if (ret == 0) {
 				++tinfo->insert;
 				SNAP_TRACK(INSERT, tinfo);
-			} else {
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(ret == WT_ROLLBACK);
-			}
+			} else
+				OP_FAILED(false);
 			break;
 		case MODIFY:
 			/*
@@ -907,13 +908,8 @@ ops(void *arg)
 			if (ret == 0) {
 				positioned = true;
 				SNAP_TRACK(MODIFY, tinfo);
-			} else {
-				positioned = false;
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(
-				    ret == WT_NOTFOUND || ret == WT_ROLLBACK);
-			}
+			} else
+				OP_FAILED(true);
 			break;
 		case READ:
 			++tinfo->search;
@@ -921,12 +917,8 @@ ops(void *arg)
 			if (ret == 0) {
 				positioned = true;
 				SNAP_TRACK(READ, tinfo);
-			} else {
-				positioned = false;
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(ret == WT_NOTFOUND);
-			}
+			} else
+				OP_FAILED(true);
 			break;
 		case REMOVE:
 remove_instead_of_truncate:
@@ -946,12 +938,8 @@ remove_instead_of_truncate:
 				 * previous state, but not necessarily set.
 				 */
 				SNAP_TRACK(REMOVE, tinfo);
-			} else {
-				positioned = false;
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(ret == WT_NOTFOUND);
-			}
+			} else
+				OP_FAILED(true);
 			break;
 		case TRUNCATE:
 			/*
@@ -1020,11 +1008,8 @@ remove_instead_of_truncate:
 			if (ret == 0) {
 				++tinfo->truncate;
 				SNAP_TRACK(TRUNCATE, tinfo);
-			} else {
-				testutil_assert(ret == WT_ROLLBACK);
-				if (intxn)
-					goto deadlock;
-			}
+			} else
+				OP_FAILED(false);
 			break;
 		case UPDATE:
 update_instead_of_chosen_op:
@@ -1041,12 +1026,8 @@ update_instead_of_chosen_op:
 			if (ret == 0) {
 				positioned = true;
 				SNAP_TRACK(UPDATE, tinfo);
-			} else {
-				positioned = false;
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(ret == WT_ROLLBACK);
-			}
+			} else
+				OP_FAILED(false);
 			break;
 		}
 
@@ -1061,9 +1042,8 @@ update_instead_of_chosen_op:
 			for (i = 0; i < j; ++i) {
 				if ((ret = nextprev(tinfo, cursor, next)) == 0)
 					continue;
-				if (ret == WT_ROLLBACK && intxn)
-					goto deadlock;
-				testutil_assert(ret == WT_NOTFOUND);
+
+				OP_FAILED(true);
 				break;
 			}
 		}
@@ -1090,9 +1070,11 @@ update_instead_of_chosen_op:
 				goto deadlock;
 		}
 
-		/* Prepare the transaction 10% of the time. */
-		/* XXX: CONFIGURE PREPARE OFF FOR NOW */
-		if (mmrand(&tinfo->rnd, 1, 10) == 0) {
+		/*
+		 * Prepare the transaction 10% of the time.
+		 * Currently doesn't work with truncation, see WT-3922.
+		 */
+		if (g.c_truncate == 0 && mmrand(&tinfo->rnd, 1, 10) == 1) {
 			ret = prepare_transaction(tinfo, session);
 			testutil_assert(ret == 0 || ret == WT_PREPARE_CONFLICT);
 			if (ret == WT_PREPARE_CONFLICT)
@@ -1138,7 +1120,7 @@ deadlock:			++tinfo->deadlock;
 
 /*
  * wts_read_scan --
- *	Read and verify all elements in a file.
+ *	Read and verify a subset of the elements in a file.
  */
 void
 wts_read_scan(void)
@@ -1182,6 +1164,7 @@ wts_read_scan(void)
 		case 0:
 		case WT_NOTFOUND:
 		case WT_ROLLBACK:
+		case WT_PREPARE_CONFLICT:
 			break;
 		default:
 			testutil_die(
@@ -1209,11 +1192,6 @@ read_row_worker(
 
 	session = cursor->session;
 
-	/* Log the operation */
-	if (g.logging == LOG_OPS)
-		(void)g.wt_api->msg_printf(g.wt_api,
-		    session, "%-10s%" PRIu64, "read", keyno);
-
 	/* Retrieve the key/value pair by key. */
 	switch (g.type) {
 	case FIX:
@@ -1254,12 +1232,15 @@ read_row_worker(
 			value->size = 1;
 		}
 		break;
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
 	default:
-		testutil_die(ret, "read_row: read row %" PRIu64, keyno);
+		return (ret);
 	}
 
+	/* Log the operation */
+	if (g.logging == LOG_OPS)
+		(void)g.wt_api->msg_printf(g.wt_api,
+		    session, "%-10s%" PRIu64, "read", keyno);
+
 #ifdef HAVE_BERKELEY_DB
 	if (!SINGLETHREADED)
 		return (ret);
@@ -1394,24 +1375,39 @@ nextprev(TINFO *tinfo, WT_CURSOR *cursor, bool next)
 		break;
 	case WT_NOTFOUND:
 		break;
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
 	default:
-		testutil_die(ret, "%s", which);
+		return (ret);
 	}
 
+	if (g.logging == LOG_OPS)
+		switch (g.type) {
+		case FIX:
+			(void)g.wt_api->msg_printf(g.wt_api,
+			    cursor->session, "%-10s%" PRIu64 " {0x%02x}",
+			    which, keyno, ((char *)value.data)[0]);
+			break;
+		case ROW:
+			(void)g.wt_api->msg_printf(g.wt_api,
+			    cursor->session, "%-10s{%.*s}, {%.*s}",
+			    which, (int)key.size, (char *)key.data,
+			    (int)value.size, (char *)value.data);
+			break;
+		case VAR:
+			(void)g.wt_api->msg_printf(g.wt_api,
+			    cursor->session, "%-10s%" PRIu64 " {%.*s}",
+			    which, keyno, (int)value.size, (char *)value.data);
+			break;
+		}
+
 #ifdef HAVE_BERKELEY_DB
 	if (!SINGLETHREADED)
 		return (ret);
 
 	{
 	WT_ITEM bdb_key, bdb_value;
-	WT_SESSION *session;
 	int notfound;
 	char *p;
 
-	session = cursor->session;
-
 	/* Retrieve the BDB key/value. */
 	bdb_np(next, &bdb_key.data, &bdb_key.size,
 	    &bdb_value.data, &bdb_value.size, &notfound);
@@ -1444,26 +1440,6 @@ mismatch:	if (g.type == ROW) {
 		print_item(" wt-value", &value);
 		testutil_die(0, NULL);
 	}
-
-	if (g.logging == LOG_OPS)
-		switch (g.type) {
-		case FIX:
-			(void)g.wt_api->msg_printf(g.wt_api,
-			    session, "%-10s%" PRIu64 " {0x%02x}", which,
-			    keyno, ((char *)value.data)[0]);
-			break;
-		case ROW:
-			(void)g.wt_api->msg_printf(
-			    g.wt_api, session, "%-10s{%.*s}, {%.*s}", which,
-			    (int)key.size, (char *)key.data,
-			    (int)value.size, (char *)value.data);
-			break;
-		case VAR:
-			(void)g.wt_api->msg_printf(g.wt_api, session,
-			    "%-10s%" PRIu64 " {%.*s}", which,
-			    keyno, (int)value.size, (char *)value.data);
-			break;
-		}
 	}
 #endif
 	return (ret);
@@ -1483,24 +1459,14 @@ row_reserve(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 		cursor->set_key(cursor, tinfo->key);
 	}
 
+	if ((ret = cursor->reserve(cursor)) != 0)
+		return (ret);
+
 	if (g.logging == LOG_OPS)
 		(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
 		    "%-10s{%.*s}", "reserve",
 		    (int)tinfo->key->size, tinfo->key->data);
 
-	switch (ret = cursor->reserve(cursor)) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	case WT_NOTFOUND:
-		return (WT_NOTFOUND);
-	default:
-		testutil_die(ret,
-		    "row_reserve: reserve row %" PRIu64 " by key",
-		    tinfo->keyno);
-	}
 	return (0);
 }
 
@@ -1516,21 +1482,13 @@ col_reserve(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 	if (!positioned)
 		cursor->set_key(cursor, tinfo->keyno);
 
+	if ((ret = cursor->reserve(cursor)) != 0)
+		return (ret);
+
 	if (g.logging == LOG_OPS)
 		(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
 		    "%-10s%" PRIu64, "reserve", tinfo->keyno);
 
-	switch (ret = cursor->reserve(cursor)) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	case WT_NOTFOUND:
-		return (WT_NOTFOUND);
-	default:
-		testutil_die(ret, "col_reserve: %" PRIu64, tinfo->keyno);
-	}
 	return (0);
 }
 
@@ -1577,19 +1535,10 @@ row_modify(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 	}
 
 	modify_build(tinfo, entries, &nentries);
-	switch (ret = cursor->modify(cursor, entries, nentries)) {
-	case 0:
-		testutil_check(cursor->get_value(cursor, tinfo->value));
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	case WT_NOTFOUND:
-		return (WT_NOTFOUND);
-	default:
-		testutil_die(ret,
-		    "row_modify: modify row %" PRIu64 " by key", tinfo->keyno);
-	}
+	if ((ret = cursor->modify(cursor, entries, nentries)) != 0)
+		return (ret);
+
+	testutil_check(cursor->get_value(cursor, tinfo->value));
 
 	if (g.logging == LOG_OPS)
 		(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
@@ -1624,25 +1573,16 @@ col_modify(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 		cursor->set_key(cursor, tinfo->keyno);
 
 	modify_build(tinfo, entries, &nentries);
-	switch (ret = cursor->modify(cursor, entries, nentries)) {
-	case 0:
-		testutil_check(cursor->get_value(cursor, tinfo->value));
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	case WT_NOTFOUND:
-		return (WT_NOTFOUND);
-	default:
-		testutil_die(ret,
-		    "col_modify: modify row %" PRIu64, tinfo->keyno);
-	}
+	if ((ret = cursor->modify(cursor, entries, nentries)) != 0)
+		return (ret);
+
+	testutil_check(cursor->get_value(cursor, tinfo->value));
 
 	if (g.logging == LOG_OPS)
 		(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
-		    "%-10s{%.*s}, {%.*s}",
+		    "%-10s%" PRIu64 ", {%.*s}",
 		    "modify",
-		    (int)tinfo->key->size, tinfo->key->data,
+		    tinfo->keyno,
 		    (int)tinfo->value->size, tinfo->value->data);
 
 #ifdef HAVE_BERKELEY_DB
@@ -1698,24 +1638,15 @@ row_truncate(TINFO *tinfo, WT_CURSOR *cursor)
 		testutil_check(c2->close(c2));
 	}
 
+	if (ret != 0)
+		return (ret);
+
 	if (g.logging == LOG_OPS)
 		(void)g.wt_api->msg_printf(g.wt_api, session,
 		    "%-10s%" PRIu64 ", %" PRIu64,
 		    "truncate",
 		    tinfo->keyno, tinfo->last);
 
-	switch (ret) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret,
-		    "row_truncate: row %" PRIu64 "-%" PRIu64,
-		    tinfo->keyno, tinfo->last);
-	}
-
 #ifdef HAVE_BERKELEY_DB
 	if (SINGLETHREADED)
 		bdb_truncate(tinfo->keyno, tinfo->last);
@@ -1724,49 +1655,6 @@ row_truncate(TINFO *tinfo, WT_CURSOR *cursor)
 }
 
 /*
- * row_update --
- *	Update a row in a row-store file.
- */
-static int
-row_update(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
-{
-	WT_DECL_RET;
-
-	if (!positioned) {
-		key_gen(tinfo->key, tinfo->keyno);
-		cursor->set_key(cursor, tinfo->key);
-	}
-	val_gen(&tinfo->rnd, tinfo->value, tinfo->keyno);
-	cursor->set_value(cursor, tinfo->value);
-
-	if (g.logging == LOG_OPS)
-		(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
-		    "%-10s{%.*s}, {%.*s}",
-		    "put",
-		    (int)tinfo->key->size, tinfo->key->data,
-		    (int)tinfo->value->size, tinfo->value->data);
-
-	switch (ret = cursor->update(cursor)) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret,
-		    "row_update: update row %" PRIu64 " by key", tinfo->keyno);
-	}
-
-#ifdef HAVE_BERKELEY_DB
-	if (SINGLETHREADED)
-		bdb_update(
-		    tinfo->key->data, tinfo->key->size,
-		    tinfo->value->data, tinfo->value->size);
-#endif
-	return (0);
-}
-
-/*
  * col_truncate --
  *	Truncate rows in a column-store file.
  */
@@ -1802,6 +1690,8 @@ col_truncate(TINFO *tinfo, WT_CURSOR *cursor)
 		ret = session->truncate(session, NULL, cursor, c2, NULL);
 		testutil_check(c2->close(c2));
 	}
+	if (ret != 0)
+		return (ret);
 
 	if (g.logging == LOG_OPS)
 		(void)g.wt_api->msg_printf(g.wt_api, session,
@@ -1809,21 +1699,44 @@ col_truncate(TINFO *tinfo, WT_CURSOR *cursor)
 		    "truncate",
 		    tinfo->keyno, tinfo->last);
 
-	switch (ret) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret,
-		    "col_truncate: row %" PRIu64 "-%" PRIu64,
-		    tinfo->keyno, tinfo->last);
+#ifdef HAVE_BERKELEY_DB
+	if (SINGLETHREADED)
+		bdb_truncate(tinfo->keyno, tinfo->last);
+#endif
+	return (0);
+}
+
+/*
+ * row_update --
+ *	Update a row in a row-store file.
+ */
+static int
+row_update(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
+{
+	WT_DECL_RET;
+
+	if (!positioned) {
+		key_gen(tinfo->key, tinfo->keyno);
+		cursor->set_key(cursor, tinfo->key);
 	}
+	val_gen(&tinfo->rnd, tinfo->value, tinfo->keyno);
+	cursor->set_value(cursor, tinfo->value);
+
+	if ((ret = cursor->update(cursor)) != 0)
+		return (ret);
+
+	if (g.logging == LOG_OPS)
+		(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
+		    "%-10s{%.*s}, {%.*s}",
+		    "put",
+		    (int)tinfo->key->size, tinfo->key->data,
+		    (int)tinfo->value->size, tinfo->value->data);
 
 #ifdef HAVE_BERKELEY_DB
 	if (SINGLETHREADED)
-		bdb_truncate(tinfo->keyno, tinfo->last);
+		bdb_update(
+		    tinfo->key->data, tinfo->key->size,
+		    tinfo->value->data, tinfo->value->size);
 #endif
 	return (0);
 }
@@ -1845,6 +1758,9 @@ col_update(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 	else
 		cursor->set_value(cursor, tinfo->value);
 
+	if ((ret = cursor->update(cursor)) != 0)
+		return (ret);
+
 	if (g.logging == LOG_OPS) {
 		if (g.type == FIX)
 			(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
@@ -1859,16 +1775,6 @@ col_update(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 			    (char *)tinfo->value->data);
 	}
 
-	switch (ret = cursor->update(cursor)) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret, "col_update: %" PRIu64, tinfo->keyno);
-	}
-
 #ifdef HAVE_BERKELEY_DB
 	if (SINGLETHREADED) {
 		key_gen(tinfo->key, tinfo->keyno);
@@ -1999,6 +1905,9 @@ row_insert(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 	val_gen(&tinfo->rnd, tinfo->value, tinfo->keyno);
 	cursor->set_value(cursor, tinfo->value);
 
+	if ((ret = cursor->insert(cursor)) != 0)
+		return (ret);
+
 	/* Log the operation */
 	if (g.logging == LOG_OPS)
 		(void)g.wt_api->msg_printf(g.wt_api, cursor->session,
@@ -2007,17 +1916,6 @@ row_insert(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 		    (int)tinfo->key->size, tinfo->key->data,
 		    (int)tinfo->value->size, tinfo->value->data);
 
-	switch (ret = cursor->insert(cursor)) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret,
-		    "row_insert: insert row %" PRIu64 " by key", tinfo->keyno);
-	}
-
 #ifdef HAVE_BERKELEY_DB
 	if (SINGLETHREADED)
 		bdb_update(
@@ -2041,15 +1939,10 @@ col_insert(TINFO *tinfo, WT_CURSOR *cursor)
 		cursor->set_value(cursor, *(uint8_t *)tinfo->value->data);
 	else
 		cursor->set_value(cursor, tinfo->value);
-	switch (ret = cursor->insert(cursor)) {
-	case 0:
-		break;
-	case WT_CACHE_FULL:
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret, "cursor.insert");
-	}
+
+	if ((ret = cursor->insert(cursor)) != 0)
+		return (ret);
+
 	testutil_check(cursor->get_key(cursor, &tinfo->keyno));
 
 	table_append(tinfo->keyno);			/* Extend the object. */
@@ -2093,23 +1986,16 @@ row_remove(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 		cursor->set_key(cursor, tinfo->key);
 	}
 
-	if (g.logging == LOG_OPS)
-		(void)g.wt_api->msg_printf(g.wt_api,
-		    cursor->session, "%-10s%" PRIu64, "remove", tinfo->keyno);
-
 	/* We use the cursor in overwrite mode, check for existence. */
 	if ((ret = cursor->search(cursor)) == 0)
 		ret = cursor->remove(cursor);
-	switch (ret) {
-	case 0:
-	case WT_NOTFOUND:
-		break;
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret,
-		    "row_remove: remove %" PRIu64 " by key", tinfo->keyno);
-	}
+
+	if (ret != 0 && ret != WT_NOTFOUND)
+		return (ret);
+
+	if (g.logging == LOG_OPS)
+		(void)g.wt_api->msg_printf(g.wt_api,
+		    cursor->session, "%-10s%" PRIu64, "remove", tinfo->keyno);
 
 #ifdef HAVE_BERKELEY_DB
 	if (SINGLETHREADED) {
@@ -2134,23 +2020,16 @@ col_remove(TINFO *tinfo, WT_CURSOR *cursor, bool positioned)
 	if (!positioned)
 		cursor->set_key(cursor, tinfo->keyno);
 
-	if (g.logging == LOG_OPS)
-		(void)g.wt_api->msg_printf(g.wt_api,
-		    cursor->session, "%-10s%" PRIu64, "remove", tinfo->keyno);
-
 	/* We use the cursor in overwrite mode, check for existence. */
 	if ((ret = cursor->search(cursor)) == 0)
 		ret = cursor->remove(cursor);
-	switch (ret) {
-	case 0:
-	case WT_NOTFOUND:
-		break;
-	case WT_ROLLBACK:
-		return (WT_ROLLBACK);
-	default:
-		testutil_die(ret,
-		    "col_remove: remove %" PRIu64 " by key", tinfo->keyno);
-	}
+
+	if (ret != 0 && ret != WT_NOTFOUND)
+		return (ret);
+
+	if (g.logging == LOG_OPS)
+		(void)g.wt_api->msg_printf(g.wt_api,
+		    cursor->session, "%-10s%" PRIu64, "remove", tinfo->keyno);
 
 #ifdef HAVE_BERKELEY_DB
 	if (SINGLETHREADED) {
diff --git a/src/third_party/wiredtiger/test/suite/test_cursor14.py b/src/third_party/wiredtiger/test/suite/test_cursor14.py
new file mode 100644
index 00000000000..25bd0cec00a
--- /dev/null
+++ b/src/third_party/wiredtiger/test/suite/test_cursor14.py
@@ -0,0 +1,60 @@
+#!/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.
+
+import wiredtiger, wttest
+from wtdataset import SimpleDataSet, ComplexDataSet, ComplexLSMDataSet
+from wtscenario import make_scenarios
+
+# test_cursor14.py
+#    Test that more than 64K cursors can be opened on a data source
+class test_cursor14(wttest.WiredTigerTestCase):
+    scenarios = make_scenarios([
+        ('file-r', dict(type='file:', keyfmt='r', dataset=SimpleDataSet)),
+        ('file-S', dict(type='file:', keyfmt='S', dataset=SimpleDataSet)),
+        ('lsm-S', dict(type='lsm:', keyfmt='S', dataset=SimpleDataSet)),
+        ('table-r', dict(type='table:', keyfmt='r', dataset=SimpleDataSet)),
+        ('table-S', dict(type='table:', keyfmt='S', dataset=SimpleDataSet)),
+        ('table-r-complex', dict(type='table:', keyfmt='r',
+            dataset=ComplexDataSet)),
+        ('table-S-complex', dict(type='table:', keyfmt='S',
+            dataset=ComplexDataSet)),
+        ('table-S-complex-lsm', dict(type='table:', keyfmt='S',
+            dataset=ComplexLSMDataSet)),
+    ])
+
+    def test_cursor14(self):
+        uri = self.type + 'cursor14'
+
+        ds = self.dataset(self, uri, 100, key_format=self.keyfmt)
+        ds.populate()
+
+        for i in xrange(66000):
+            cursor = self.session.open_cursor(uri, None, None)
+
+if __name__ == '__main__':
+    wttest.run()
diff --git a/src/third_party/wiredtiger/test/suite/test_prepare04.py b/src/third_party/wiredtiger/test/suite/test_prepare04.py
new file mode 100644
index 00000000000..af5dd12b1e5
--- /dev/null
+++ b/src/third_party/wiredtiger/test/suite/test_prepare04.py
@@ -0,0 +1,122 @@
+#!/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.
+#
+# test_prepare04.py
+#   Prepare: prepare conflict with update and read operations
+#
+
+import random
+from suite_subprocess import suite_subprocess
+import wiredtiger, wttest
+from wtscenario import make_scenarios
+
+def timestamp_str(t):
+    return '%x' % t
+
+class test_prepare04(wttest.WiredTigerTestCase, suite_subprocess):
+    tablename = 'test_prepare_cursor'
+    uri = 'table:' + tablename
+    before_ts = timestamp_str(150)
+    prepare_ts = timestamp_str(200)
+    after_ts = timestamp_str(250)
+
+    types = [
+        ('col', dict(extra_config=',log=(enabled=false),key_format=r')),
+        ('lsm', dict(extra_config=',log=(enabled=false),type=lsm')),
+        ('row', dict(extra_config=',log=(enabled=false)')),
+    ]
+
+    # Various begin_transaction config
+    txncfg = [
+        ('before_ts', dict(txn_config='isolation=snapshot,read_timestamp=' + before_ts, after_ts=False)),
+        ('after_ts', dict(txn_config='isolation=snapshot,read_timestamp=' + after_ts, after_ts=True)),
+        ('no_ts', dict(txn_config='isolation=snapshot', after_ts=True)),
+    ]
+
+    preparecfg = [
+        ('ignore_false', dict(ignore_config=',ignore_prepare=false', ignore=False)),
+        ('ignore_true', dict(ignore_config=',ignore_prepare=true', ignore=True)),
+    ]
+    conn_config = 'log=(enabled)'
+
+    scenarios = make_scenarios(types, txncfg, preparecfg)
+
+    def test_prepare_conflict(self):
+        if not wiredtiger.timestamp_build():
+            self.skipTest('requires a timestamp build')
+
+        self.session.create(self.uri,
+            'key_format=i,value_format=i' + self.extra_config)
+        c = self.session.open_cursor(self.uri)
+
+        # Insert keys 1..100 each with timestamp=key, in some order
+        orig_keys = range(1, 101)
+        keys = orig_keys[:]
+        random.shuffle(keys)
+
+        k = 1
+        self.session.begin_transaction()
+        c[k] = 1
+        self.session.commit_transaction('commit_timestamp=' + timestamp_str(100))
+
+        # Everything up to and including timestamp 100 has been committed.
+        self.assertTimestampsEqual(self.conn.query_timestamp(), timestamp_str(100))
+
+        # Bump the oldest timestamp, we're not going back...
+        self.conn.set_timestamp('oldest_timestamp=' + timestamp_str(100))
+
+        # make prepared updates.
+        k = 1
+        self.session.begin_transaction('isolation=snapshot')
+        c.set_key(1)
+        c.set_value(2)
+        c.update()
+        self.session.prepare_transaction('prepare_timestamp=' + self.prepare_ts)
+        conflictmsg = '/conflict between concurrent operations/'
+        preparemsg = '/conflict with a prepared update/'
+
+        #'''
+        # Verify data visibility from a different session/transaction.
+        s_other = self.conn.open_session()
+        c_other = s_other.open_cursor(self.uri, None)
+        s_other.begin_transaction(self.txn_config + self.ignore_config)
+        c_other.set_key(1)
+        if self.ignore == False and self.after_ts == True:
+            self.assertRaises(wiredtiger.WiredTigerError, lambda:c_other.search())
+        else:
+            c_other.search()
+            self.assertTrue(c_other.get_value() == 1)
+        c_other.set_value(3)
+        self.assertRaises(wiredtiger.WiredTigerError, lambda:c_other.update())
+        s_other.commit_transaction()
+        #'''
+
+        self.session.commit_transaction('commit_timestamp=' + timestamp_str(300))
+
+if __name__ == '__main__':
+    wttest.run()
diff --git a/src/third_party/wiredtiger/test/suite/test_timestamp04.py b/src/third_party/wiredtiger/test/suite/test_timestamp04.py
index 48ec7fac9a6..83ed4e904a6 100644
--- a/src/third_party/wiredtiger/test/suite/test_timestamp04.py
+++ b/src/third_party/wiredtiger/test/suite/test_timestamp04.py
@@ -32,6 +32,7 @@
 
 from suite_subprocess import suite_subprocess
 import wiredtiger, wttest
+from wiredtiger import stat
 from wtscenario import make_scenarios
 
 def timestamp_str(t):
@@ -98,7 +99,7 @@ class test_timestamp04(wttest.WiredTigerTestCase, suite_subprocess):
 
     def ConnectionOpen(self, cacheSize):
         self.home = '.'
-        conn_params = 'create,' + \
+        conn_params = 'create,statistics=(fast),' + \
             cacheSize + ',error_prefix="%s" %s' % (self.shortid(), self.conn_config)
         try:
             self.conn = wiredtiger.wiredtiger_open(self.home, conn_params)
@@ -164,6 +165,12 @@ class test_timestamp04(wttest.WiredTigerTestCase, suite_subprocess):
         stable_ts = timestamp_str(key_range / 2)
         self.conn.set_timestamp('stable_timestamp=' + stable_ts)
         self.conn.rollback_to_stable()
+        stat_cursor = self.session.open_cursor('statistics:', None, None)
+        calls = stat_cursor[stat.conn.txn_rollback_to_stable][2]
+        upd_aborted = stat_cursor[stat.conn.txn_rollback_upd_aborted][2]
+        stat_cursor.close()
+        self.assertEqual(calls, 1)
+        self.assertTrue(upd_aborted >= key_range/2)
 
         # Check that we see the inserted value (i.e. 1) for all the keys in
         # non-timestamp tables.
@@ -224,9 +231,20 @@ class test_timestamp04(wttest.WiredTigerTestCase, suite_subprocess):
         # Scenario: 4
         # Advance the stable_timestamp by a quarter range and rollback.
         # Three-fourths of the later timestamps will be rolled back.
-        stable_ts = timestamp_str(key_range + key_range / 4)
+        rolled_range = key_range + key_range / 4
+        stable_ts = timestamp_str(rolled_range)
         self.conn.set_timestamp('stable_timestamp=' + stable_ts)
         self.conn.rollback_to_stable()
+        stat_cursor = self.session.open_cursor('statistics:', None, None)
+        calls = stat_cursor[stat.conn.txn_rollback_to_stable][2]
+        upd_aborted = stat_cursor[stat.conn.txn_rollback_upd_aborted][2]
+        stat_cursor.close()
+        self.assertEqual(calls, 2)
+        #
+        # We rolled back half on the earlier call and now three-quarters on
+        # this call, which is one and one quarter of all keys rolled back.
+        #
+        self.assertTrue(upd_aborted >= rolled_range)
 
         # Check that we see the updated value (i.e. 2) for all the keys in
         # non-timestamped tables.
diff --git a/src/third_party/wiredtiger/test/suite/test_timestamp10.py b/src/third_party/wiredtiger/test/suite/test_timestamp10.py
index a798f5ff355..02b22e6afbe 100644
--- a/src/third_party/wiredtiger/test/suite/test_timestamp10.py
+++ b/src/third_party/wiredtiger/test/suite/test_timestamp10.py
@@ -27,7 +27,7 @@
 # OTHER DEALINGS IN THE SOFTWARE.
 #
 # test_timestamp10.py
-#   Timestamps: Saving and querying the checkpoint recovery timestamp
+#   Timestamps: Saving and querying the last checkpoint and recovery timestamps
 #
 
 import fnmatch, os, shutil
@@ -101,6 +101,8 @@ class test_timestamp10(wttest.WiredTigerTestCase, suite_subprocess):
                 ',stable_timestamp=' + timestamp_str(ts))
             # This forces a different checkpoint timestamp for each table.
             self.session.checkpoint()
+            q = self.conn.query_timestamp('get=last_checkpoint')
+            self.assertTimestampsEqual(q, timestamp_str(ts))
 
         # Copy to a new database and then recover.
         self.copy_dir(".", "RESTART")