diff options
Diffstat (limited to 'src/backend/access/transam/xlog.c')
| -rw-r--r-- | src/backend/access/transam/xlog.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 6cf441534cc..92822a192b0 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -845,6 +845,8 @@ static void WALInsertLockAcquireExclusive(void); static void WALInsertLockRelease(void); static void WALInsertLockUpdateInsertingAt(XLogRecPtr insertingAt); +static void fsync_pgdata(char *datadir); + /* * Insert an XLOG record represented by an already-constructed chain of data * chunks. This is a low-level routine; to construct the WAL record header @@ -5910,6 +5912,18 @@ StartupXLOG(void) (errmsg("database system was interrupted; last known up at %s", str_time(ControlFile->time)))); + /* + * If we previously crashed, there might be data which we had written, + * intending to fsync it, but which we had not actually fsync'd yet. + * Therefore, a power failure in the near future might cause earlier + * unflushed writes to be lost, even though more recent data written to + * disk from here on would be persisted. To avoid that, fsync the entire + * data directory. + */ + if (ControlFile->state != DB_SHUTDOWNED && + ControlFile->state != DB_SHUTDOWNED_IN_RECOVERY) + fsync_pgdata(data_directory); + /* This is just to allow attaching to startup process with a debugger */ #ifdef XLOG_REPLAY_DELAY if (ControlFile->state != DB_SHUTDOWNED) @@ -11123,3 +11137,31 @@ SetWalWriterSleeping(bool sleeping) XLogCtl->WalWriterSleeping = sleeping; SpinLockRelease(&XLogCtl->info_lck); } + +/* + * Issue fsync recursively on PGDATA and all its contents. + */ +static void +fsync_pgdata(char *datadir) +{ + if (!enableFsync) + return; + + /* + * If possible, hint to the kernel that we're soon going to fsync + * the data directory and its contents. + */ +#if defined(HAVE_SYNC_FILE_RANGE) || \ + (defined(USE_POSIX_FADVISE) && defined(POSIX_FADV_DONTNEED)) + walkdir(datadir, pre_sync_fname); +#endif + + /* + * Now we do the fsync()s in the same order. + * + * It's important to fsync the destination directory itself as individual + * file fsyncs don't guarantee that the directory entry for the file is + * synced. + */ + walkdir(datadir, fsync_fname); +} |