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Diffstat (limited to 'src/backend/access/transam/xlogrecovery.c')
-rw-r--r--src/backend/access/transam/xlogrecovery.c37
1 files changed, 28 insertions, 9 deletions
diff --git a/src/backend/access/transam/xlogrecovery.c b/src/backend/access/transam/xlogrecovery.c
index dbe93947627..02d1b2cd6d8 100644
--- a/src/backend/access/transam/xlogrecovery.c
+++ b/src/backend/access/transam/xlogrecovery.c
@@ -1935,6 +1935,31 @@ ApplyWalRecord(XLogReaderState *xlogreader, XLogRecord *record, TimeLineID *repl
XLogRecoveryCtl->lastReplayedTLI = *replayTLI;
SpinLockRelease(&XLogRecoveryCtl->info_lck);
+ /* ------
+ * Wakeup walsenders:
+ *
+ * On the standby, the WAL is flushed first (which will only wake up
+ * physical walsenders) and then applied, which will only wake up logical
+ * walsenders.
+ *
+ * Indeed, logical walsenders on standby can't decode and send data until
+ * it's been applied.
+ *
+ * Physical walsenders don't need to be woken up during replay unless
+ * cascading replication is allowed and time line change occurred (so that
+ * they can notice that they are on a new time line).
+ *
+ * That's why the wake up conditions are for:
+ *
+ * - physical walsenders in case of new time line and cascade
+ * replication is allowed
+ * - logical walsenders in case cascade replication is allowed (could not
+ * be created otherwise)
+ * ------
+ */
+ if (AllowCascadeReplication())
+ WalSndWakeup(switchedTLI, true);
+
/*
* If rm_redo called XLogRequestWalReceiverReply, then we wake up the
* receiver so that it notices the updated lastReplayedEndRecPtr and sends
@@ -1958,12 +1983,6 @@ ApplyWalRecord(XLogReaderState *xlogreader, XLogRecord *record, TimeLineID *repl
*/
RemoveNonParentXlogFiles(xlogreader->EndRecPtr, *replayTLI);
- /*
- * Wake up any walsenders to notice that we are on a new timeline.
- */
- if (AllowCascadeReplication())
- WalSndWakeup();
-
/* Reset the prefetcher. */
XLogPrefetchReconfigure();
}
@@ -3050,9 +3069,9 @@ ReadRecord(XLogPrefetcher *xlogprefetcher, int emode,
{
/*
* When we find that WAL ends in an incomplete record, keep track
- * of that record. After recovery is done, we'll write a record to
- * indicate to downstream WAL readers that that portion is to be
- * ignored.
+ * of that record. After recovery is done, we'll write a record
+ * to indicate to downstream WAL readers that that portion is to
+ * be ignored.
*
* However, when ArchiveRecoveryRequested = true, we're going to
* switch to a new timeline at the end of recovery. We will only