Fix another bug regarding when pages can be evicted: have reconcilition track the maximum transaction ID on the page (regardless of whether it is skipped). A page can only be evicted when it is clean and has no updates that are too new.

refs #884

2 files changed, 12 insertions, 21 deletions

diff --git a/src/btree/rec_write.c b/src/btree/rec_write.c
index 81a4ec7a025..43b5532ad1a 100644
--- a/src/btree/rec_write.c
+++ b/src/btree/rec_write.c
@@ -668,26 +668,12 @@ static inline int
 __rec_txn_read(
     WT_SESSION_IMPL *session, WT_RECONCILE *r, WT_UPDATE *upd, WT_UPDATE **updp)
 {
-	uint64_t txnid;
 	int skip, retried;
 
 	retried = 0;
-retry:	*updp = __wt_txn_read_skip(session, upd, &skip);
-	if (!skip) {
-		/*
-		 * Track the largest transaction ID written to disk for this
-		 * page.  We store this in the page at the end of
-		 * reconciliation if no updates are skipped.  It is used to
-		 * avoid evicting a clean page from memory with changes that
-		 * are required to satisfy a snapshot read.
-		 */
-		if (*updp != NULL) {
-			txnid = (*updp)->txnid;
-			if (TXNID_LT(r->max_txn, txnid))
-				r->max_txn = txnid;
-		}
+retry:	*updp = __wt_txn_read_skip(session, upd, &r->max_txn, &skip);
+	if (!skip)
 		return (0);
-	}
 
 	/*
 	 * If skipping this update will cause reconciliation to quit, update
diff --git a/src/include/txn.i b/src/include/txn.i
index 8ec1f52bff4..0c51751ccd2 100644
--- a/src/include/txn.i
+++ b/src/include/txn.i
@@ -170,17 +170,22 @@ __wt_txn_visible(WT_SESSION_IMPL *session, uint64_t id)
  *	and report whether there are an uncommitted changes in the list.
  */
 static inline WT_UPDATE *
-__wt_txn_read_skip(WT_SESSION_IMPL *session, WT_UPDATE *upd, int *skipp)
+__wt_txn_read_skip(
+    WT_SESSION_IMPL *session, WT_UPDATE *upd, uint64_t *max_txn, int *skipp)
 {
 	WT_UPDATE *first_upd;
 
 	*skipp = 0;
 	for (first_upd = NULL; upd != NULL; upd = upd->next)
 		if (upd->txnid != WT_TXN_ABORTED) {
-			if (!__wt_txn_visible(session, upd->txnid))
-				*skipp = 1;
-			else if (first_upd == NULL)
-				first_upd = upd;
+			if (TXNID_LT(*max_txn, upd->txnid))
+				*max_txn = upd->txnid;
+			if (first_upd == NULL) {
+				if (__wt_txn_visible(session, upd->txnid))
+					first_upd = upd;
+				else
+					*skipp = 1;
+			}
 		}
 
 	return (first_upd);