WT-2954 Enable fast appends with small in-memory pages. (#3094)

Eviction tuning to help improve the workload

4 files changed, 22 insertions, 18 deletions

diff --git a/src/btree/bt_read.c b/src/btree/bt_read.c
index 679f20bdac5..90188498535 100644
--- a/src/btree/bt_read.c
+++ b/src/btree/bt_read.c
@@ -327,25 +327,28 @@ __evict_force_check(WT_SESSION_IMPL *session, WT_REF *ref)
 	if (__wt_hazard_count(session, page) > 1)
 		return (false);
 
+	/* If we can do an in-memory split, do it. */
+	if (__wt_leaf_page_can_split(session, page))
+		return (true);
+	if (page->memory_footprint < btree->maxmempage)
+		return (false);
+
+	/* Bump the oldest ID, we're about to do some visibility checks. */
+	WT_IGNORE_RET(__wt_txn_update_oldest(session, 0));
+
 	/*
 	 * Allow some leeway if the transaction ID isn't moving forward since
 	 * it is unlikely eviction will be able to evict the page. Don't keep
 	 * skipping the page indefinitely or large records can lead to
 	 * extremely large memory footprints.
 	 */
-	if (page->memory_footprint < btree->maxmempage &&
+	if (page->modify->update_restored &&
 	    page->modify->last_eviction_id == __wt_txn_oldest_id(session))
 		return (false);
 
-	if (page->memory_footprint < btree->maxmempage)
-		return (__wt_leaf_page_can_split(session, page));
-
 	/* Trigger eviction on the next page release. */
 	__wt_page_evict_soon(session, ref);
 
-	/* Bump the oldest ID, we're about to do some visibility checks. */
-	WT_IGNORE_RET(__wt_txn_update_oldest(session, 0));
-
 	/* If eviction cannot succeed, don't try. */
 	return (__wt_page_can_evict(session, ref, NULL));
 }
diff --git a/src/btree/bt_split.c b/src/btree/bt_split.c
index ea667460966..017c820ea29 100644
--- a/src/btree/bt_split.c
+++ b/src/btree/bt_split.c
@@ -1582,6 +1582,13 @@ __split_multi_inmem(
 	 */
 	page->modify->first_dirty_txn = WT_TXN_FIRST;
 
+	/*
+	 * If the new page is modified, save the oldest ID from reconciliation
+	 * to avoid repeatedly attempting eviction on the same page.
+	 */
+	page->modify->last_eviction_id = orig->modify->last_eviction_id;
+	page->modify->update_restored = 1;
+
 err:	/* Free any resources that may have been cached in the cursor. */
 	WT_TRET(__wt_btcur_close(&cbt, true));
 
@@ -2245,14 +2252,6 @@ __wt_split_rewrite(WT_SESSION_IMPL *session, WT_REF *ref, WT_MULTI *multi)
 	WT_ERR(__split_multi_inmem(session, page, multi, new));
 
 	/*
-	 * If the new page is modified, save the oldest ID from reconciliation
-	 * to avoid repeatedly attempting eviction on the same page.
-	 */
-	if (new->page->modify != NULL)
-		new->page->modify->last_eviction_id =
-		    page->modify->last_eviction_id;
-
-	/*
 	 * The rewrite succeeded, we can no longer fail.
 	 *
 	 * Finalize the move, discarding moved update lists from the original
diff --git a/src/evict/evict_lru.c b/src/evict/evict_lru.c
index 8ca73160cd5..6c99f3a13dc 100644
--- a/src/evict/evict_lru.c
+++ b/src/evict/evict_lru.c
@@ -1284,8 +1284,8 @@ __evict_push_candidate(WT_SESSION_IMPL *session,
  *	Get a few page eviction candidates from a single underlying file.
  */
 static int
-__evict_walk_file(WT_SESSION_IMPL *session,
-    WT_EVICT_QUEUE *queue, u_int max_entries, u_int *slotp)
+__evict_walk_file(WT_SESSION_IMPL *session, WT_EVICT_QUEUE *queue,
+    u_int max_entries, u_int *slotp)
 {
 	WT_BTREE *btree;
 	WT_CACHE *cache;
@@ -1559,7 +1559,7 @@ __evict_get_ref(
 	server_only = is_server && !WT_EVICT_HAS_WORKERS(session);
 	urgent_ok = (!is_app && !is_server) ||
 	    !WT_EVICT_HAS_WORKERS(session) ||
-	    __wt_cache_aggressive(session);
+	    (is_app && __wt_cache_aggressive(session));
 	urgent_queue = cache->evict_urgent_queue;
 	*btreep = NULL;
 	*refp = NULL;
diff --git a/src/include/btmem.h b/src/include/btmem.h
index 278d0e50ee8..84c91097a99 100644
--- a/src/include/btmem.h
+++ b/src/include/btmem.h
@@ -430,6 +430,8 @@ struct __wt_page_modify {
 #define	WT_PM_REC_MULTIBLOCK	2	/* Reconciliation: multiple blocks */
 #define	WT_PM_REC_REPLACE	3	/* Reconciliation: single block */
 	uint8_t rec_result;		/* Reconciliation state */
+
+	uint8_t update_restored;	/* Page created by restoring updates */
 };
 
 /*