From: Bharath Rupireddy Date: Fri, 4 Mar 2022 13:22:41 +0900 Subject: [PATCH v11 2/5] Add checkpoint and redo LSN to LogCheckpointEnd log message It is useful (for debugging purposes) if the checkpoint end message has the checkpoint LSN(end) and REDO LSN(start). It gives more context while analyzing checkpoint-related issues. The pg_controldata gives the last checkpoint LSN and REDO LSN, but having this info alongside the log message helps analyze issues that happened previously, connect the dots and identify the root cause. --- src/backend/access/transam/xlog.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 3987aa81de..2e1123fd42 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -6120,7 +6120,8 @@ LogCheckpointEnd(bool restartpoint) "%d WAL file(s) added, %d removed, %d recycled; " "write=%ld.%03d s, sync=%ld.%03d s, total=%ld.%03d s; " "sync files=%d, longest=%ld.%03d s, average=%ld.%03d s; " - "distance=%d kB, estimate=%d kB", + "distance=%d kB, estimate=%d kB; " + "lsn=%X/%X, redo lsn=%X/%X", CheckpointStats.ckpt_bufs_written, (double) CheckpointStats.ckpt_bufs_written * 100 / NBuffers, CheckpointStats.ckpt_segs_added, @@ -6133,14 +6134,18 @@ LogCheckpointEnd(bool restartpoint) longest_msecs / 1000, (int) (longest_msecs % 1000), average_msecs / 1000, (int) (average_msecs % 1000), (int) (PrevCheckPointDistance / 1024.0), - (int) (CheckPointDistanceEstimate / 1024.0)))); + (int) (CheckPointDistanceEstimate / 1024.0), + /* we are the only updator of these variables */ + LSN_FORMAT_ARGS(ControlFile->checkPoint), + LSN_FORMAT_ARGS(ControlFile->checkPointCopy.redo)))); else ereport(LOG, (errmsg("checkpoint complete: wrote %d buffers (%.1f%%); " "%d WAL file(s) added, %d removed, %d recycled; " "write=%ld.%03d s, sync=%ld.%03d s, total=%ld.%03d s; " "sync files=%d, longest=%ld.%03d s, average=%ld.%03d s; " - "distance=%d kB, estimate=%d kB", + "distance=%d kB, estimate=%d kB; " + "lsn=%X/%X, redo lsn=%X/%X", CheckpointStats.ckpt_bufs_written, (double) CheckpointStats.ckpt_bufs_written * 100 / NBuffers, CheckpointStats.ckpt_segs_added, @@ -6153,7 +6158,10 @@ LogCheckpointEnd(bool restartpoint) longest_msecs / 1000, (int) (longest_msecs % 1000), average_msecs / 1000, (int) (average_msecs % 1000), (int) (PrevCheckPointDistance / 1024.0), - (int) (CheckPointDistanceEstimate / 1024.0)))); + (int) (CheckPointDistanceEstimate / 1024.0), + /* we are the only updator of these variables */ + LSN_FORMAT_ARGS(ControlFile->checkPoint), + LSN_FORMAT_ARGS(ControlFile->checkPointCopy.redo)))); } /* -- 2.27.0 ----Next_Part(Fri_Mar__4_14_10_38_2022_481)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v11-0003-Change-location-to-lsn-in-pg_controldata.patch"