Import wiredtiger: bc0337ed0085ea2d7b00f73deb2f726b4ffbee1b from branch mongodb-3.8

ref: d1027489d8..bc0337ed00
for: 3.7.1

WT-3607       Compact skips all in-cache blocks with associated disk images
WT-3658       Fixed-sized strings can be stored without a trailing NUL
WT-3761       Review when cursor operations force evict pages
WT-3762       Allow the oldest_timestamp to be moved backwards.

1 files changed, 17 insertions, 7 deletions

diff --git a/src/third_party/wiredtiger/src/txn/txn_timestamp.c b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
index 5a39a6d84dc..6735946fbb3 100644
--- a/src/third_party/wiredtiger/src/txn/txn_timestamp.c
+++ b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
@@ -292,7 +292,7 @@ __wt_txn_global_query_timestamp(
  *	maintained for current or future readers).
  */
 int
-__wt_txn_update_pinned_timestamp(WT_SESSION_IMPL *session)
+__wt_txn_update_pinned_timestamp(WT_SESSION_IMPL *session, bool force)
 {
 	WT_DECL_RET;
 	WT_TXN_GLOBAL *txn_global;
@@ -321,7 +321,7 @@ __wt_txn_update_pinned_timestamp(WT_SESSION_IMPL *session)
 	} else
 		__wt_timestamp_set(&pinned_timestamp, &active_timestamp);
 
-	if (txn_global->has_pinned_timestamp) {
+	if (txn_global->has_pinned_timestamp && !force) {
 		WT_WITH_TIMESTAMP_READLOCK(session, &txn_global->rwlock,
 		    __wt_timestamp_set(
 			&last_pinned_timestamp, &txn_global->pinned_timestamp));
@@ -332,7 +332,7 @@ __wt_txn_update_pinned_timestamp(WT_SESSION_IMPL *session)
 	}
 
 	__wt_writelock(session, &txn_global->rwlock);
-	if (!txn_global->has_pinned_timestamp || __wt_timestamp_cmp(
+	if (!txn_global->has_pinned_timestamp || force || __wt_timestamp_cmp(
 	    &txn_global->pinned_timestamp, &pinned_timestamp) < 0) {
 		__wt_timestamp_set(
 		    &txn_global->pinned_timestamp, &pinned_timestamp);
@@ -377,11 +377,14 @@ __wt_txn_global_set_timestamp(WT_SESSION_IMPL *session, const char *cfg[])
 
 #ifdef HAVE_TIMESTAMPS
 	{
+	WT_CONFIG_ITEM cval;
 	WT_TXN_GLOBAL *txn_global;
 	wt_timestamp_t commit_ts, oldest_ts, stable_ts;
 	wt_timestamp_t last_oldest_ts, last_stable_ts;
+	bool force;
 
 	txn_global = &S2C(session)->txn_global;
+
 	/*
 	 * Parsing will initialize the timestamp to zero even if
 	 * it is not configured.
@@ -393,6 +396,13 @@ __wt_txn_global_set_timestamp(WT_SESSION_IMPL *session, const char *cfg[])
 	WT_RET(__wt_txn_parse_timestamp(
 	    session, "stable", &stable_ts, &stable_cval));
 
+	WT_RET(__wt_config_gets_def(session,
+	    cfg, "force", 0, &cval));
+	force = cval.val != 0;
+
+	if (force)
+		goto set;
+
 	__wt_readlock(session, &txn_global->rwlock);
 
 	__wt_timestamp_set(&last_oldest_ts, &txn_global->oldest_timestamp);
@@ -460,7 +470,7 @@ __wt_txn_global_set_timestamp(WT_SESSION_IMPL *session, const char *cfg[])
 	if (!has_commit && !has_oldest && !has_stable)
 		return (0);
 
-	__wt_writelock(session, &txn_global->rwlock);
+set:	__wt_writelock(session, &txn_global->rwlock);
 	/*
 	 * This method can be called from multiple threads, check that we are
 	 * moving the global timestamps forwards.
@@ -479,7 +489,7 @@ __wt_txn_global_set_timestamp(WT_SESSION_IMPL *session, const char *cfg[])
 	}
 
 	if (has_oldest && (!txn_global->has_oldest_timestamp ||
-	    __wt_timestamp_cmp(
+	    force || __wt_timestamp_cmp(
 	    &oldest_ts, &txn_global->oldest_timestamp) > 0)) {
 		__wt_timestamp_set(&txn_global->oldest_timestamp, &oldest_ts);
 		txn_global->has_oldest_timestamp = true;
@@ -489,7 +499,7 @@ __wt_txn_global_set_timestamp(WT_SESSION_IMPL *session, const char *cfg[])
 	}
 
 	if (has_stable && (!txn_global->has_stable_timestamp ||
-	    __wt_timestamp_cmp(
+	    force || __wt_timestamp_cmp(
 	    &stable_ts, &txn_global->stable_timestamp) > 0)) {
 		__wt_timestamp_set(&txn_global->stable_timestamp, &stable_ts);
 		txn_global->has_stable_timestamp = true;
@@ -500,7 +510,7 @@ __wt_txn_global_set_timestamp(WT_SESSION_IMPL *session, const char *cfg[])
 	__wt_writeunlock(session, &txn_global->rwlock);
 
 	if (has_oldest || has_stable)
-		WT_RET(__wt_txn_update_pinned_timestamp(session));
+		WT_RET(__wt_txn_update_pinned_timestamp(session, force));
 	}
 	return (0);
 #else