Re: BUG #14941: Vacuum crashes

On 12/01/2017 05:09 PM, lyes(dot)amd(at)gmail(dot)com wrote:
> The following bug has been logged on the website:
>
> Bug reference: 14941
> Logged by: Lyes Ameddah
> Email address: lyes(dot)amd(at)gmail(dot)com
> PostgreSQL version: 9.6.0

The current minor version in 9.6 branch is 9.6. You're missing a year
worth of bugfixes ...

> Operating system: CentOs 7
> Description:
>
> Hello,
>
> I make a complete empty once a week in an automated way and it happens that
> the vacuum is stuck on a table (perhaps another process has a lock first).
>

1) Completely empty what?

2) Do you mean autovacuum or manual vacuum?

3) Do you see waiting locks in pg_locks catalog while this is happening?

SELECT * FROM pg_locks WHERE NOT granted;

>
> The behavior I would like to see is that the void ignores this table and
> moves to another instead of being blocked.
>

I believe autovacuum should not block waiting for a heavy-weight lock on
a table since this commit that went into 9.1:

https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=32896c40ca766146312b28a5a0eb3f66ca0300ed

So I'm wondering what problem you're running into.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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