diff options
| -rw-r--r-- | src/backend/access/transam/xlogprefetcher.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/src/backend/access/transam/xlogprefetcher.c b/src/backend/access/transam/xlogprefetcher.c index f3428888d2b..959e4094667 100644 --- a/src/backend/access/transam/xlogprefetcher.c +++ b/src/backend/access/transam/xlogprefetcher.c @@ -487,8 +487,8 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn) */ nonblocking = XLogReaderHasQueuedRecordOrError(reader); - /* Certain records act as barriers for all readahead. */ - if (nonblocking && replaying_lsn < prefetcher->no_readahead_until) + /* Readahead is disabled until we replay past a certain point. */ + if (nonblocking && replaying_lsn <= prefetcher->no_readahead_until) return LRQ_NEXT_AGAIN; record = XLogReadAhead(prefetcher->reader, nonblocking); @@ -496,8 +496,13 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn) { /* * We can't read any more, due to an error or lack of data in - * nonblocking mode. + * nonblocking mode. Don't try to read ahead again until + * we've replayed everything already decoded. */ + if (nonblocking && prefetcher->reader->decode_queue_tail) + prefetcher->no_readahead_until = + prefetcher->reader->decode_queue_tail->lsn; + return LRQ_NEXT_AGAIN; } |