From 195d4932c6d6ec3787b3543a8322ff0025d7daaf Mon Sep 17 00:00:00 2001 From: Konstantin Knizhnik Date: Wed, 28 Jun 2023 09:04:13 +0300 Subject: [PATCH] Set LwLSN after WAL records when redo is performed or skipped (#4579) ## Problem See #4516 Inspecting log it is possible to notice that if lwlsn is set to the beginning of applied WAL record, then incorrect version of the page is loaded: ``` 2023-06-27 18:36:51.930 GMT [3273945] CONTEXT: WAL redo at 0/14AF6F0 for Heap/INSERT: off 2 flags 0x01; blkref #0: rel 1663/5/1259, blk 0 FPW 2023-06-27 18:36:51.930 GMT [3273945] LOG: Do REDO block 0 of rel 1663/5/1259 fork 0 at LSN 0/**014AF6F0**..0/014AFA60 2023-06-27 18:37:02.173 GMT [3273963] LOG: Read blk 0 in rel 1663/5/1259 fork 0 (request LSN 0/**014AF6F0**): lsn=0/**0143C7F8** at character 22 2023-06-27 18:37:47.780 GMT [3273945] LOG: apply WAL record at 0/1BB8F38 xl_tot_len=188, xl_prev=0/1BB8EF8 2023-06-27 18:37:47.780 GMT [3273945] CONTEXT: WAL redo at 0/1BB8F38 for Heap/INPLACE: off 2; blkref #0: rel 1663/5/1259, blk 0 2023-06-27 18:37:47.780 GMT [3273945] LOG: Do REDO block 0 of rel 1663/5/1259 fork 0 at LSN 0/01BB8F38..0/01BB8FF8 2023-06-27 18:37:47.780 GMT [3273945] CONTEXT: WAL redo at 0/1BB8F38 for Heap/INPLACE: off 2; blkref #0: rel 1663/5/1259, blk 0 2023-06-27 18:37:47.780 GMT [3273945] PANIC: invalid lp ``` ## Summary of changes 1. Use end record LSN for both cases 2. Update lwlsn for relation metadata ## Checklist before requesting a review - [ ] I have performed a self-review of my code. - [ ] If it is a core feature, I have added thorough tests. - [ ] Do we need to implement analytics? if so did you add the relevant metrics to the dashboard? - [ ] If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section. ## Checklist before merging - [ ] Do not forget to reformat commit message to not include the above checklist --- pgxn/neon/pagestore_smgr.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/pgxn/neon/pagestore_smgr.c b/pgxn/neon/pagestore_smgr.c index 528d4eb051..79dec0881d 100644 --- a/pgxn/neon/pagestore_smgr.c +++ b/pgxn/neon/pagestore_smgr.c @@ -2675,7 +2675,6 @@ bool neon_redo_read_buffer_filter(XLogReaderState *record, uint8 block_id) { XLogRecPtr end_recptr = record->EndRecPtr; - XLogRecPtr prev_end_recptr = record->ReadRecPtr - 1; RelFileNode rnode; ForkNumber forknum; BlockNumber blkno; @@ -2719,16 +2718,15 @@ neon_redo_read_buffer_filter(XLogReaderState *record, uint8 block_id) no_redo_needed = buffer < 0; - /* we don't have the buffer in memory, update lwLsn past this record */ + /* In both cases st lwlsn past this WAL record */ + SetLastWrittenLSNForBlock(end_recptr, rnode, forknum, blkno); + + /* we don't have the buffer in memory, update lwLsn past this record, + * also evict page fro file cache + */ if (no_redo_needed) - { - SetLastWrittenLSNForBlock(end_recptr, rnode, forknum, blkno); lfc_evict(rnode, forknum, blkno); - } - else - { - SetLastWrittenLSNForBlock(prev_end_recptr, rnode, forknum, blkno); - } + LWLockRelease(partitionLock); @@ -2736,7 +2734,10 @@ neon_redo_read_buffer_filter(XLogReaderState *record, uint8 block_id) if (get_cached_relsize(rnode, forknum, &relsize)) { if (relsize < blkno + 1) + { update_cached_relsize(rnode, forknum, blkno + 1); + SetLastWrittenLSNForRelation(end_recptr, rnode, forknum); + } } else { @@ -2768,6 +2769,7 @@ neon_redo_read_buffer_filter(XLogReaderState *record, uint8 block_id) Assert(nbresponse->n_blocks > blkno); set_cached_relsize(rnode, forknum, nbresponse->n_blocks); + SetLastWrittenLSNForRelation(end_recptr, rnode, forknum); elog(SmgrTrace, "Set length to %d", nbresponse->n_blocks); }