diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 4a8a2f6098..6499eabe4d 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -5652,7 +5652,7 @@ StartupXLOG(void) if (didCrash) pgstat_discard_stats(); else - pgstat_restore_stats(); + pgstat_restore_stats(checkPoint.redo); lastFullPageWrites = checkPoint.fullPageWrites; diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index 228cdf73f7..81484222cf 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -94,6 +94,7 @@ #include #include "access/xact.h" +#include "access/xlog.h" #include "lib/dshash.h" #include "pgstat.h" #include "port/atomics.h" @@ -171,8 +172,8 @@ typedef struct PgStat_SnapshotEntry * ---------- */ -static void pgstat_write_statsfile(void); -static void pgstat_read_statsfile(void); +static void pgstat_write_statsfile(XLogRecPtr redo); +static void pgstat_read_statsfile(XLogRecPtr redo); static void pgstat_reset_after_failure(void); @@ -448,9 +449,9 @@ static const PgStat_KindInfo pgstat_kind_infos[PGSTAT_NUM_KINDS] = { * Should only be called by the startup process or in single user mode. */ void -pgstat_restore_stats(void) +pgstat_restore_stats(XLogRecPtr redo) { - pgstat_read_statsfile(); + pgstat_read_statsfile(redo); } /* @@ -526,7 +527,7 @@ pgstat_before_server_shutdown(int code, Datum arg) if (code == 0) { pgStatLocal.shmem->is_shutdown = true; - pgstat_write_statsfile(); + pgstat_write_statsfile(GetRedoRecPtr()); } } @@ -1349,7 +1350,7 @@ write_chunk(FILE *fpout, void *ptr, size_t len) * stats so locking is not required. */ static void -pgstat_write_statsfile(void) +pgstat_write_statsfile(XLogRecPtr redo) { FILE *fpout; int32 format_id; @@ -1366,7 +1367,8 @@ pgstat_write_statsfile(void) /* we're shutting down, so it's ok to just override this */ pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_NONE; - elog(DEBUG2, "writing stats file \"%s\"", statfile); + elog(DEBUG2, "writing stats file \"%s\" with redo %X/%X", statfile, + LSN_FORMAT_ARGS(redo)); /* * Open the statistics temp file to write out the current values. @@ -1387,6 +1389,9 @@ pgstat_write_statsfile(void) format_id = PGSTAT_FILE_FORMAT_ID; write_chunk_s(fpout, &format_id); + /* Write the redo LSN, used to cross check the file read */ + write_chunk_s(fpout, &redo); + /* Write various stats structs for fixed number of objects */ for (int kind = PGSTAT_KIND_FIRST_VALID; kind <= PGSTAT_KIND_LAST; kind++) { @@ -1501,18 +1506,20 @@ read_chunk(FILE *fpin, void *ptr, size_t len) * stats so locking is not required. */ static void -pgstat_read_statsfile(void) +pgstat_read_statsfile(XLogRecPtr redo) { FILE *fpin; int32 format_id; bool found; const char *statfile = PGSTAT_STAT_PERMANENT_FILENAME; PgStat_ShmemControl *shmem = pgStatLocal.shmem; + XLogRecPtr file_redo; /* shouldn't be called from postmaster */ Assert(IsUnderPostmaster || !IsPostmasterEnvironment); - elog(DEBUG2, "reading stats file \"%s\"", statfile); + elog(DEBUG2, "reading stats file \"%s\" with redo %X/%X", statfile, + LSN_FORMAT_ARGS(redo)); /* * Try to open the stats file. If it doesn't exist, the backends simply @@ -1550,6 +1557,22 @@ pgstat_read_statsfile(void) goto error; } + /* + * Read the redo LSN stored in the file. + */ + if (!read_chunk_s(fpin, &file_redo)) + { + elog(WARNING, "could not read redo LSN"); + goto error; + } + + if (file_redo != redo) + { + elog(WARNING, "found incorrect redo LSN %X/%X (expected %X/%X)", + LSN_FORMAT_ARGS(file_redo), LSN_FORMAT_ARGS(redo)); + goto error; + } + /* * We found an existing statistics file. Read it and put all the stats * data into place. diff --git a/src/include/pgstat.h b/src/include/pgstat.h index 6b99bb8aad..043d39a565 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -11,6 +11,7 @@ #ifndef PGSTAT_H #define PGSTAT_H +#include "access/xlogdefs.h" #include "datatype/timestamp.h" #include "portability/instr_time.h" #include "postmaster/pgarch.h" /* for MAX_XFN_CHARS */ @@ -235,7 +236,7 @@ typedef struct PgStat_TableXactStatus * ------------------------------------------------------------ */ -#define PGSTAT_FILE_FORMAT_ID 0x01A5BCAD +#define PGSTAT_FILE_FORMAT_ID 0x01A5BCAE typedef struct PgStat_ArchiverStats { @@ -466,7 +467,7 @@ extern Size StatsShmemSize(void); extern void StatsShmemInit(void); /* Functions called during server startup / shutdown */ -extern void pgstat_restore_stats(void); +extern void pgstat_restore_stats(XLogRecPtr redo); extern void pgstat_discard_stats(void); extern void pgstat_before_server_shutdown(int code, Datum arg);