Horton

Re: BUG #17255: Server crashes in index_delete_sort_cmp() due to race condition with vacuum

Peter Geoghegan <pg@bowt.ie>

View thread View on postgr.es
From: Peter Geoghegan <pg@bowt.ie>
To: Andres Freund <andres@anarazel.de>
Cc: Dmitry Dolgov <9erthalion6@gmail.com>, Alexander Lakhin <exclusion@gmail.com>, PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Date: 2021-10-30T21:46:13Z
Lists: pgsql-bugs 
On Sat, Oct 30, 2021 at 2:39 PM Andres Freund <andres@anarazel.de> wrote:
> The crash is somewhere in pg_class, which is also manually VACUUMed by the
> test, which could trigger the issue we found in the other thread. The likely
> reason the loop in the repro is needed is that that'll push one of the indexes
> on pg_class over the 512kb/min_parallel_index_scan_size boundary to start
> using paralell vacuum.

Quite possible, but I can't rule out the possibility that it's
actually this other bug, since as you say this is pg_class, a system
catalog index:

https://www.postgresql.org/message-id/CAH2-WzkjjCoq5Y4LeeHJcjYJVxGm3M3SAWZ0%3D6J8K1FPSC9K0w%40mail.gmail.com

I am in too much of a hurry right now to spend the 5 minutes it would
take to confirm either way. (Even if it's not this other bug, I needed
to remind you of its existence anyway.)

-- 
Peter Geoghegan

Commits

  1. vacuumlazy.c: Standardize rel_pages terminology.

  2. vacuumlazy.c: document vistest and OldestXmin.

  3. heap pruning: Only call BufferGetBlockNumber() once.

  4. Fix possible HOT corruption when RECENTLY_DEAD changes to DEAD while pruning.

  5. Assert redirect pointers are sensible after heap_page_prune().

  6. Remove tupgone special case from vacuumlazy.c.

  7. Recycle nbtree pages deleted during same VACUUM.

  8. snapshot scalability: Don't compute global horizons while building snapshots.

  9. Refactor heap_page_prune so that instead of changing item states on-the-fly,