Re: admin control over cancelling autovacuum when blocked by a lock

On Mon, 29 Apr 2019 at 22:02, John Lumby <johnlumby(at)hotmail(dot)com> wrote:

> If a regular backend worker becomes blocked waiting for a lock held by an
> autovacuum worker,
> then , depending on some decision made by deadlock detector,
> the autovacuum worker may be signalled to terminate
>
> This results in messages such as these in the statement log
>
>
> ERROR: canceling autovacuum task
> CONTEXT: automatic vacuum of table "somedb.aschema.thistable"
>
> Is there any configuration parameter which controls this?
> including deferring or even completely eliminating this cancelling?
> so that, in the eliminate case, the waiter would simply go on waiting
> until the autovacuum eventually finishes "thistable"?
>
> I have not seen any parameter to do this.
> Note that I don't mean some parameter which affects all locking behaviour,
> only this autovacuum case.
>

Why would you want this?

If the autovacuum is cancelled, it will re-execute again in the near
future, once your interrupting SQL has released locks.

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