diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c index 007974ea99..0211a68640 100644 --- a/src/backend/access/transam/xlogutils.c +++ b/src/backend/access/transam/xlogutils.c @@ -639,128 +639,6 @@ XLogTruncateRelation(RelFileNode rnode, ForkNumber forkNum, forget_invalid_pages(rnode, forkNum, nblocks); } -/* - * Read 'count' bytes from WAL into 'buf', starting at location 'startptr' - * in timeline 'tli'. - * - * Will open, and keep open, one WAL segment stored in the static file - * descriptor 'sendFile'. This means if XLogRead is used once, there will - * always be one descriptor left open until the process ends, but never - * more than one. - * - * XXX This is very similar to pg_waldump's XLogDumpXLogRead and to XLogRead - * in walsender.c but for small differences (such as lack of elog() in - * frontend). Probably these should be merged at some point. - */ -static void -XLogReadOld(char *buf, int segsize, TimeLineID tli, XLogRecPtr startptr, - Size count) -{ - char *p; - XLogRecPtr recptr; - Size nbytes; - - /* state maintained across calls */ - static int sendFile = -1; - static XLogSegNo sendSegNo = 0; - static TimeLineID sendTLI = 0; - static uint32 sendOff = 0; - - Assert(segsize == wal_segment_size); - - p = buf; - recptr = startptr; - nbytes = count; - - while (nbytes > 0) - { - uint32 startoff; - int segbytes; - int readbytes; - - startoff = XLogSegmentOffset(recptr, segsize); - - /* Do we need to switch to a different xlog segment? */ - if (sendFile < 0 || !XLByteInSeg(recptr, sendSegNo, segsize) || - sendTLI != tli) - { - char path[MAXPGPATH]; - - if (sendFile >= 0) - close(sendFile); - - XLByteToSeg(recptr, sendSegNo, segsize); - - XLogFilePath(path, tli, sendSegNo, segsize); - - sendFile = BasicOpenFile(path, O_RDONLY | PG_BINARY); - - if (sendFile < 0) - { - if (errno == ENOENT) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("requested WAL segment %s has already been removed", - path))); - else - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not open file \"%s\": %m", - path))); - } - sendOff = 0; - sendTLI = tli; - } - - /* Need to seek in the file? */ - if (sendOff != startoff) - { - if (lseek(sendFile, (off_t) startoff, SEEK_SET) < 0) - { - char path[MAXPGPATH]; - int save_errno = errno; - - XLogFilePath(path, tli, sendSegNo, segsize); - errno = save_errno; - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not seek in log segment %s to offset %u: %m", - path, startoff))); - } - sendOff = startoff; - } - - /* How many bytes are within this segment? */ - if (nbytes > (segsize - startoff)) - segbytes = segsize - startoff; - else - segbytes = nbytes; - - pgstat_report_wait_start(WAIT_EVENT_WAL_READ); - readbytes = read(sendFile, p, segbytes); - pgstat_report_wait_end(); - if (readbytes <= 0) - { - char path[MAXPGPATH]; - int save_errno = errno; - - XLogFilePath(path, tli, sendSegNo, segsize); - errno = save_errno; - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not read from log segment %s, offset %u, length %lu: %m", - path, sendOff, (unsigned long) segbytes))); - } - - /* Update state for read */ - recptr += readbytes; - - sendOff += readbytes; - nbytes -= readbytes; - p += readbytes; - } -} - /* * Determine which timeline to read an xlog page from and set the * XLogReaderState's currTLI to that timeline ID. diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index b21b143f99..76a5477389 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -252,9 +252,6 @@ static void WalSndSegmentOpen(XLogSegNo nextSegNo, WALSegmentContext *segcxt, TimeLineID *tli_p, int *file_p); -static void XLogReadOld(WALSegmentContext *segcxt, char *buf, - XLogRecPtr startptr, Size count); - /* Initialize walsender process before entering the main command loop */ void InitWalSender(void) @@ -2377,191 +2374,6 @@ WalSndKill(int code, Datum arg) SpinLockRelease(&walsnd->mutex); } -/* - * Read 'count' bytes from WAL into 'buf', starting at location 'startptr' - * - * XXX probably this should be improved to suck data directly from the - * WAL buffers when possible. - * - * Will open, and keep open, one WAL segment stored in the global file - * descriptor sendFile. This means if XLogRead is used once, there will - * always be one descriptor left open until the process ends, but never - * more than one. - */ -static void -XLogReadOld(WALSegmentContext *segcxt, char *buf, XLogRecPtr startptr, Size count) -{ - char *p; - XLogRecPtr recptr; - Size nbytes; - XLogSegNo segno; - -retry: - p = buf; - recptr = startptr; - nbytes = count; - - while (nbytes > 0) - { - uint32 startoff; - int segbytes; - int readbytes; - - startoff = XLogSegmentOffset(recptr, segcxt->ws_segsize); - - if (sendSeg->ws_file < 0 || - !XLByteInSeg(recptr, sendSeg->ws_segno, segcxt->ws_segsize)) - { - char path[MAXPGPATH]; - - /* Switch to another logfile segment */ - if (sendSeg->ws_file >= 0) - close(sendSeg->ws_file); - - XLByteToSeg(recptr, sendSeg->ws_segno, segcxt->ws_segsize); - - /*------- - * When reading from a historic timeline, and there is a timeline - * switch within this segment, read from the WAL segment belonging - * to the new timeline. - * - * For example, imagine that this server is currently on timeline - * 5, and we're streaming timeline 4. The switch from timeline 4 - * to 5 happened at 0/13002088. In pg_wal, we have these files: - * - * ... - * 000000040000000000000012 - * 000000040000000000000013 - * 000000050000000000000013 - * 000000050000000000000014 - * ... - * - * In this situation, when requested to send the WAL from - * segment 0x13, on timeline 4, we read the WAL from file - * 000000050000000000000013. Archive recovery prefers files from - * newer timelines, so if the segment was restored from the - * archive on this server, the file belonging to the old timeline, - * 000000040000000000000013, might not exist. Their contents are - * equal up to the switchpoint, because at a timeline switch, the - * used portion of the old segment is copied to the new file. - *------- - */ - sendSeg->ws_tli = sendTimeLine; - if (sendTimeLineIsHistoric) - { - XLogSegNo endSegNo; - - XLByteToSeg(sendTimeLineValidUpto, endSegNo, segcxt->ws_segsize); - if (sendSeg->ws_segno == endSegNo) - sendSeg->ws_tli = sendTimeLineNextTLI; - } - - XLogFilePath(path, sendSeg->ws_tli, sendSeg->ws_segno, segcxt->ws_segsize); - - sendSeg->ws_file = BasicOpenFile(path, O_RDONLY | PG_BINARY); - if (sendSeg->ws_file < 0) - { - /* - * If the file is not found, assume it's because the standby - * asked for a too old WAL segment that has already been - * removed or recycled. - */ - if (errno == ENOENT) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("requested WAL segment %s has already been removed", - XLogFileNameP(sendSeg->ws_tli, sendSeg->ws_segno)))); - else - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not open file \"%s\": %m", - path))); - } - sendSeg->ws_off = 0; - } - - /* Need to seek in the file? */ - if (sendSeg->ws_off != startoff) - { - if (lseek(sendSeg->ws_file, (off_t) startoff, SEEK_SET) < 0) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not seek in log segment %s to offset %u: %m", - XLogFileNameP(sendSeg->ws_tli, sendSeg->ws_segno), - startoff))); - sendSeg->ws_off = startoff; - } - - /* How many bytes are within this segment? */ - if (nbytes > (segcxt->ws_segsize - startoff)) - segbytes = segcxt->ws_segsize - startoff; - else - segbytes = nbytes; - - pgstat_report_wait_start(WAIT_EVENT_WAL_READ); - readbytes = read(sendSeg->ws_file, p, segbytes); - pgstat_report_wait_end(); - if (readbytes < 0) - { - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not read from log segment %s, offset %u, length %zu: %m", - XLogFileNameP(sendSeg->ws_tli, sendSeg->ws_segno), - sendSeg->ws_off, (Size) segbytes))); - } - else if (readbytes == 0) - { - ereport(ERROR, - (errcode(ERRCODE_DATA_CORRUPTED), - errmsg("could not read from log segment %s, offset %u: read %d of %zu", - XLogFileNameP(sendSeg->ws_tli, sendSeg->ws_segno), - sendSeg->ws_off, readbytes, (Size) segbytes))); - } - - /* Update state for read */ - recptr += readbytes; - - sendSeg->ws_off += readbytes; - nbytes -= readbytes; - p += readbytes; - } - - /* - * After reading into the buffer, check that what we read was valid. We do - * this after reading, because even though the segment was present when we - * opened it, it might get recycled or removed while we read it. The - * read() succeeds in that case, but the data we tried to read might - * already have been overwritten with new WAL records. - */ - XLByteToSeg(startptr, segno, segcxt->ws_segsize); - CheckXLogRemoved(segno, ThisTimeLineID); - - /* - * During recovery, the currently-open WAL file might be replaced with the - * file of the same name retrieved from archive. So we always need to - * check what we read was valid after reading into the buffer. If it's - * invalid, we try to open and read the file again. - */ - if (am_cascading_walsender) - { - WalSnd *walsnd = MyWalSnd; - bool reload; - - SpinLockAcquire(&walsnd->mutex); - reload = walsnd->needreload; - walsnd->needreload = false; - SpinLockRelease(&walsnd->mutex); - - if (reload && sendSeg->ws_file >= 0) - { - close(sendSeg->ws_file); - sendSeg->ws_file = -1; - - goto retry; - } - } -} - /* * Callback for XLogRead() to open the next segment. */ diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c index 4c49d1acf4..39686c235c 100644 --- a/src/bin/pg_waldump/pg_waldump.c +++ b/src/bin/pg_waldump/pg_waldump.c @@ -321,128 +321,6 @@ WALDumpOpenSegment(XLogSegNo nextSegNo, WALSegmentContext *segcxt, fname, strerror(errno)); } -/* - * Read count bytes from a segment file in the specified directory, for the - * given timeline, containing the specified record pointer; store the data in - * the passed buffer. - */ -static void -XLogDumpXLogRead(const char *directory, TimeLineID timeline_id, - XLogRecPtr startptr, char *buf, Size count) -{ - char *p; - XLogRecPtr recptr; - Size nbytes; - - static int sendFile = -1; - static XLogSegNo sendSegNo = 0; - static uint32 sendOff = 0; - - p = buf; - recptr = startptr; - nbytes = count; - - while (nbytes > 0) - { - uint32 startoff; - int segbytes; - int readbytes; - - startoff = XLogSegmentOffset(recptr, WalSegSz); - - if (sendFile < 0 || !XLByteInSeg(recptr, sendSegNo, WalSegSz)) - { - char fname[MAXFNAMELEN]; - int tries; - - /* Switch to another logfile segment */ - if (sendFile >= 0) - close(sendFile); - - XLByteToSeg(recptr, sendSegNo, WalSegSz); - - XLogFileName(fname, timeline_id, sendSegNo, WalSegSz); - - /* - * In follow mode there is a short period of time after the server - * has written the end of the previous file before the new file is - * available. So we loop for 5 seconds looking for the file to - * appear before giving up. - */ - for (tries = 0; tries < 10; tries++) - { - sendFile = open_file_in_directory(directory, fname); - if (sendFile >= 0) - break; - if (errno == ENOENT) - { - int save_errno = errno; - - /* File not there yet, try again */ - pg_usleep(500 * 1000); - - errno = save_errno; - continue; - } - /* Any other error, fall through and fail */ - break; - } - - if (sendFile < 0) - fatal_error("could not find file \"%s\": %s", - fname, strerror(errno)); - sendOff = 0; - } - - /* Need to seek in the file? */ - if (sendOff != startoff) - { - if (lseek(sendFile, (off_t) startoff, SEEK_SET) < 0) - { - int err = errno; - char fname[MAXPGPATH]; - - XLogFileName(fname, timeline_id, sendSegNo, WalSegSz); - - fatal_error("could not seek in log file %s to offset %u: %s", - fname, startoff, strerror(err)); - } - sendOff = startoff; - } - - /* How many bytes are within this segment? */ - if (nbytes > (WalSegSz - startoff)) - segbytes = WalSegSz - startoff; - else - segbytes = nbytes; - - readbytes = read(sendFile, p, segbytes); - if (readbytes <= 0) - { - int err = errno; - char fname[MAXPGPATH]; - int save_errno = errno; - - XLogFileName(fname, timeline_id, sendSegNo, WalSegSz); - errno = save_errno; - - if (readbytes < 0) - fatal_error("could not read from log file %s, offset %u, length %d: %s", - fname, sendOff, segbytes, strerror(err)); - else if (readbytes == 0) - fatal_error("could not read from log file %s, offset %u: read %d of %zu", - fname, sendOff, readbytes, (Size) segbytes); - } - - /* Update state for read */ - recptr += readbytes; - - sendOff += readbytes; - nbytes -= readbytes; - p += readbytes; - } -} - /* * XLogReader read_page callback */ -- 2.20.1