Thank you, v5 didn't find any issues at all. One thing: for my 29 indexes, the tool generated output 3.5 GiB. I guess many INFO messages should be downgraded to something like DEBUG1?
On Fri, Jul 30, 2021 at 2:35 AM Heikki Linnakangas <hlinnaka@iki.fi> wrote:
On 29/07/2021 21:34, Nikolay Samokhvalov wrote: > I was trying to check a bunch of GINs on some production after switching > from Ubuntu 16.04 to 18.04 and got many errors. So decided to check for > 16.04 first (that is still used on prod for that DB), without any > OS/glibc changes. > > On 16.04, I still saw errors and it was not really expected because this > should mean that production is corrupted too. So, REINDEX should fix it. > But it didn't -- see output below. I cannot give data and thinking how > to create a synthetic demo of this. Any suggestions? > > And is this a sign that the tool is wrong rather that we have a real > corruption cases? (I assume if we did, we would see no errors after > REINDEXing -- of course, if GIN itself doesn't have bugs). > > Env: Ubuntu 16.04 (so, glibc 2.27), Postgres 12.7, patch from Heikki > slightly adjusted to work with PG12 ( > https://gitlab.com/postgres/postgres/-/merge_requests/5 > <https://gitlab.com/postgres/postgres/-/merge_requests/5>) snippet used > to run amcheck: > https://gitlab.com/-/snippets/2001962 > <https://gitlab.com/-/snippets/2001962> (see file #3)
Almost certainly the tool is wrong. We went back and forth a few times with Pawel, fixing various bugs in the amcheck patch at this thread: https://www.postgresql.org/message-id/9fdbb584-1e10-6a55-ecc2-9ba8b5dca1cf%40iki.fi. Can you try again with the latest patch version from that thread, please? That's v5-0001-Amcheck-for-GIN-13stable.patch.
