Horton

Re: collect_corrupt_items_vacuum.patch

Alexander Law <exclusion@gmail.com>

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From: Alexander Lakhin <exclusion@gmail.com>
To: Alexander Korotkov <aekorotkov@gmail.com>
Cc: Daniel Gustafsson <daniel@yesql.se>, Daniel Shelepanov <deniel1495@mail.ru>, Nikita Malakhov <hukutoc@gmail.com>, Michael Paquier <michael@paquier.xyz>, Robert Haas <robertmhaas@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Andres Freund <andres@anarazel.de>
Date: 2023-12-04T10:00:00Z
Lists: pgsql-hackers 
Hi Alexander,

04.12.2023 03:23, Alexander Korotkov wrote:
> I managed to reproduce this on a Linux VM.  This problem should arise
> because in extension I don't have access to ProcArrayStruct.  So, my
> code is iterating the whole PGPROC's array.  I reimplemented the new
> horizon calculation function in the core with usage of
> ProcArrayStruct.  Now it doesn't fall for me.  Please, recheck.

Yes, v4 works for me as well (thousands of iterations passed).
Thank you!

Though the test passes even without manipulations with the PROC_IN_VACUUM
flag in pg_visibility.c (maybe the test is not good enough to show why
those manipulations are needed).
I also couldn't see where VISHORIZON_DATA_STRICT comes into play...

Best regards,
Alexander

Commits

  1. Fix GetStrictOldestNonRemovableTransactionId() on standby

  2. Fix typo in GetRunningTransactionData()

  3. Optimize memory access in GetRunningTransactionData()

  4. Fix false reports in pg_visibility

  5. Fix indentation