On Mon, 15 Sept 2025 at 18:27, Andrey Borodin <[email protected]> wrote: > > > > > On 15 Sep 2025, at 17:56, Kirill Reshke <[email protected]> wrote: > > > > I suggest removing this custom FPW support. > > I agree that extra message adds no value. Generic FPW message has the same > "for verification" details too. > I've checked if there are any other similar cases, but found non FPW > indications in other resource managers.
Thanks for review > Maybe a litter comment about why we don't describe anything in presence of > FPW would be good. But nearby code is not very verbose... > I dunno. Looks like after removing code, this comment about FPW will be just out of place. We already have documentation about pg_waldump in general, don't we? By the way, I have spotted a few new places which can be enhanced in GIN redo & waldump. PFA V2 series. 0001: Basically same as v1-0001 0002: During my work, I have to modify GIN pg_waldump to get more information about some wal records. In v2-0002 there are two modifications in XLOG_GIN_UPDATE_META_PAGE and XLOG_GIN_INSERT_LISTPAGE, which has added the most value (for me). I also used to display meta-page info, but I discarded this custom info display logic, as it adds little value(is it?) 0003: Small nitpick. I copy-pasted this code from pg core to my cpp project and the compiler noticed the `payload` variable was not used after the last modification. I find this true. 0004: Remove the RelFileLocator field of ginxlogUpdateMeta walrecord. It is not used in relay logic. 0005: Small nitpicky patch to document ginxlogInsertListPage's backup blocks. 0006: CREATE_PTREE always includes page contents in its walrecord on HEAD (correct me if i'm wrong, but this is what I see in source and in by-hand testing). In this patch I completely removes XLOG_GIN_CREATE_PTREE custom logic and replace it with a general FPW mechanism. This patch reduces wal record size in case wal_compression is enabled. Before 0006: ``` reshke@yezzey-cbdb-bench:~$ /home/reshke/pg19/bin/bin/pg_waldump -f -r GIN db/pg_wal/000000010000000000000005 | grep create_p -i rmgr: Gin len (rec/tot): 8117/ 8117, tx: 831, lsn: 0/05AF9B18, prev 0/05AF9A98, desc: CREATE_PTREE size: 8064, blkref #0: rel 1663/16384/16541 blk 517 rmgr: Gin len (rec/tot): 8117/ 8117, tx: 831, lsn: 0/05B13078, prev 0/05B13030, desc: CREATE_PTREE size: 8064, blkref #0: rel 1663/16384/16541 blk 525 rmgr: Gin len (rec/tot): 8117/ 8117, tx: 831, lsn: 0/05B2C5D8, prev 0/05B2C590, desc: CREATE_PTREE size: 8064, blkref #0: rel 1663/16384/16541 blk 533 rmgr: Gin len (rec/tot): 8117/ 8117, tx: 831, lsn: 0/05B45B20, prev 0/05B45AD8, desc: CREATE_PTREE size: 8064, blkref #0: rel 1663/16384/16541 blk 541 ``` After 0006: ``` reshke@yezzey-cbdb-bench:~$ /home/reshke/pg19/bin/bin/pg_waldump -f -r GIN db/pg_wal/000000010000000000000004 | grep CREATE rmgr: Gin len (rec/tot): 51/ 410, tx: 795, lsn: 0/041FE560, prev 0/041FE4E0, desc: CREATE_PTREE , blkref #0: rel 1663/16384/16527 blk 517 FPW rmgr: Gin len (rec/tot): 51/ 410, tx: 795, lsn: 0/042000B8, prev 0/04200070, desc: CREATE_PTREE , blkref #0: rel 1663/16384/16527 blk 525 FPW rmgr: Gin len (rec/tot): 51/ 410, tx: 795, lsn: 0/04201BF8, prev 0/04201BB0, desc: CREATE_PTREE , blkref #0: rel 1663/16384/16527 blk 533 FPW rmgr: Gin len (rec/tot): 51/ 410, tx: 795, lsn: 0/04203750, prev 0/04203708, desc: CREATE_PTREE , blkref #0: rel 1663/16384/16527 blk 541 FPW ``` Size reduced 8117-> 410 bytes. WDYT? -- Best regards, Kirill Reshke
v2-0002-Better-gin-pg_waldump.patch
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v2-0004-Remove-locator.patch
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v2-0003-fix-oversight-of-631118fe1e8f.patch
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v2-0001-Remove-custom-full-page-write-decribption-from-GI.patch
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v2-0005-Add-comment-to-ginxlogInsertListPage.patch
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v2-0006-Remove-custom-logic-for-ginxlogCreatePostingTree-.patch
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