diff options
Diffstat (limited to 'src/backend/storage/buffer/bufmgr.c')
| -rw-r--r-- | src/backend/storage/buffer/bufmgr.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c index 5a237d56063..7778dde3e57 100644 --- a/src/backend/storage/buffer/bufmgr.c +++ b/src/backend/storage/buffer/bufmgr.c @@ -541,8 +541,11 @@ PrefetchSharedBuffer(SMgrRelation smgr_reln, * Try to initiate an asynchronous read. This returns false in * recovery if the relation file doesn't exist. */ - if (smgrprefetch(smgr_reln, forkNum, blockNum)) + if ((io_direct_flags & IO_DIRECT_DATA) == 0 && + smgrprefetch(smgr_reln, forkNum, blockNum)) + { result.initiated_io = true; + } #endif /* USE_PREFETCH */ } else @@ -588,11 +591,11 @@ PrefetchSharedBuffer(SMgrRelation smgr_reln, * the kernel and therefore didn't really initiate I/O, and no way to know when * the I/O completes other than using synchronous ReadBuffer(). * - * 3. Otherwise, the buffer wasn't already cached by PostgreSQL, and either + * 3. Otherwise, the buffer wasn't already cached by PostgreSQL, and * USE_PREFETCH is not defined (this build doesn't support prefetching due to - * lack of a kernel facility), or the underlying relation file wasn't found and - * we are in recovery. (If the relation file wasn't found and we are not in - * recovery, an error is raised). + * lack of a kernel facility), direct I/O is enabled, or the underlying + * relation file wasn't found and we are in recovery. (If the relation file + * wasn't found and we are not in recovery, an error is raised). */ PrefetchBufferResult PrefetchBuffer(Relation reln, ForkNumber forkNum, BlockNumber blockNum) @@ -5440,6 +5443,9 @@ ScheduleBufferTagForWriteback(WritebackContext *context, BufferTag *tag) { PendingWriteback *pending; + if (io_direct_flags & IO_DIRECT_DATA) + return; + /* * Add buffer to the pending writeback array, unless writeback control is * disabled. |