Re: Changed behavior in rewriteheap - Mailing list pgsql-hackers

From Erik Nordström
Subject Re: Changed behavior in rewriteheap
Date
Msg-id CACAa4V+G3-1dZV7-VnaGE0MwOGA-+piZkus_xj9vjGNO7r9BRQ@mail.gmail.com
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In response to Re: Changed behavior in rewriteheap  (Heikki Linnakangas <hlinnaka@iki.fi>)
Responses Re: Changed behavior in rewriteheap
List pgsql-hackers
On Fri, Nov 22, 2024 at 2:26 PM Heikki Linnakangas <hlinnaka@iki.fi> wrote:
On 22/11/2024 15:02, Matthias van de Meent wrote:
> I think I'd go with a patch like attached, where the bulk writer
> registers that it started with .relsize pages in the relfork, and use
> that for smgrextend() decisions. It now also records pages_written as
> a separate but accurate value.

Looks good to me. Eric, can you confirm that Matthias's patch fixes the
problem for you?


Yes, it solves the issue so it looks good.

Just a minor nit: the code uses both blokno as local variable for pending_writes[i].blkno and directly accessing pending_writes[i].blkno. Maybe it is better to just use the local variable. For example, change

++ b/src/backend/storage/smgr/bulk_write.c
@@ -304,7 +304,8 @@ smgr_bulk_flush(BulkWriteState *bulkstate)
                        }
 
                        smgrextend(bulkstate->smgr, bulkstate->forknum, blkno, page, true);
-                       bulkstate->relsize = pending_writes[i].blkno + 1;
+                       bulkstate->relsize++;
+                       Assert(bulkstate->relsize == blkno + 1);

Just a suggestion.

Thanks for the quick action!

-Erik

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