diff options
| author | Thomas Munro <tmunro@postgresql.org> | 2020-09-25 18:49:43 +1200 |
|---|---|---|
| committer | Thomas Munro <tmunro@postgresql.org> | 2020-09-25 19:00:15 +1200 |
| commit | dee663f7843902535a15ae366cede8b4089f1144 (patch) | |
| tree | 24858a312bb174c78ad7047ab52656a673f3de4e /src/include/access/clog.h | |
| parent | ca7f8e2b86e5f15a40b67e6199d714f45a467ff1 (diff) | |
Defer flushing of SLRU files.
Previously, we called fsync() after writing out individual pg_xact,
pg_multixact and pg_commit_ts pages due to cache pressure, leading to
regular I/O stalls in user backends and recovery. Collapse requests for
the same file into a single system call as part of the next checkpoint,
as we already did for relation files, using the infrastructure developed
by commit 3eb77eba. This can cause a significant improvement to
recovery performance, especially when it's otherwise CPU-bound.
Hoist ProcessSyncRequests() up into CheckPointGuts() to make it clearer
that it applies to all the SLRU mini-buffer-pools as well as the main
buffer pool. Rearrange things so that data collected in CheckpointStats
includes SLRU activity.
Also remove the Shutdown{CLOG,CommitTS,SUBTRANS,MultiXact}() functions,
because they were redundant after the shutdown checkpoint that
immediately precedes them. (I'm not sure if they were ever needed, but
they aren't now.)
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> (parts)
Tested-by: Jakub Wartak <Jakub.Wartak@tomtom.com>
Discussion: https://postgr.es/m/CA+hUKGLJ=84YT+NvhkEEDAuUtVHMfQ9i-N7k_o50JmQ6Rpj_OQ@mail.gmail.com
Diffstat (limited to 'src/include/access/clog.h')
| -rw-r--r-- | src/include/access/clog.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/src/include/access/clog.h b/src/include/access/clog.h index 2db8acb189f..6c840cbf299 100644 --- a/src/include/access/clog.h +++ b/src/include/access/clog.h @@ -12,6 +12,7 @@ #define CLOG_H #include "access/xlogreader.h" +#include "storage/sync.h" #include "lib/stringinfo.h" /* @@ -50,6 +51,8 @@ extern void CheckPointCLOG(void); extern void ExtendCLOG(TransactionId newestXact); extern void TruncateCLOG(TransactionId oldestXact, Oid oldestxid_datoid); +extern int clogsyncfiletag(const FileTag *ftag, char *path); + /* XLOG stuff */ #define CLOG_ZEROPAGE 0x00 #define CLOG_TRUNCATE 0x10 |