Re: BUG #18616: Long-running hash index build can not be interrupted

Alexander Lakhin <exclusion@gmail.com>

From: Alexander Lakhin <exclusion@gmail.com>

To: Pavel Borisov <pashkin.elfe@gmail.com>

Cc: pgsql-bugs@lists.postgresql.org

Date: 2024-09-13T18:00:00Z

Lists: pgsql-bugs

Commits

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Allow _h_indexbuild() to be interrupted.
- fae55f0bb385 18.0 landed
- 418c6a2c72d2 17.0 landed
- e0857898b87b 15.9 landed
- d23109f4bd65 16.5 landed
- b49013f2e86a 14.14 landed
- b27215dbb42b 13.17 landed
- 813ade54806c 12.21 landed

Hi Pavel,

13.09.2024 17:51, Pavel Borisov wrote:
>
>
>     Reproduced on all supported versions.
>
> I was unable to reproduce it on my machine with these settings. Tried statement timeouts 30-120s. Index build appears 
> to be in interruptible phase on my system.
> But could you check in your environment with the following patch?
>

Thank you for paying attention to this!

Yes, the patch works for me. The query is interrupted as expected.
But I wonder, why don't you the see same?

Could you please show the server log, with the following change applied and
log_statement = 'all'
backtrace_functions = 'ProcessInterrupts'
?

--- a/src/backend/access/hash/hashsort.c
+++ b/src/backend/access/hash/hashsort.c
@@ -125,6 +125,7 @@ _h_indexbuild(HSpool *hspool, Relation heapRel)
      uint32      hashkey = 0;
  #endif

+elog(LOG, "_h_indexbuild() start");
      tuplesort_performsort(hspool->sortstate);

      while ((itup = tuplesort_getindextuple(hspool->sortstate, true)) != NULL)
@@ -151,4 +152,5 @@ _h_indexbuild(HSpool *hspool, Relation heapRel)
pgstat_progress_update_param(PROGRESS_CREATEIDX_TUPLES_DONE,
                                       ++tups_done);
      }
+elog(LOG, "_h_indexbuild() end; tups_done: %ld", tups_done);
  }

Best regards,
Alexander