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

John Lumby <johnlumby@hotmail.com> writes:
> On 04/29/2019 07:15 PM, Simon Riggs wrote:
>> Why would you want this?

> Because it greatly reduces rate of growth of certain indexes in some
> workloads
> (based on test in which I modified the code to change the cancel to a
> plain WARNING)

[ raised eyebrow... ]  Shouldn't do so, I think.  What exactly are you
doing that's causing the cancel?

> I *think* when an autovacuum worker is cancelled,  all or most of the work
> it did on its last table is undone  --  true?

If you're losing index cleanup
work, it suggests that you're repeatedly executing DDL that requires
exclusive lock on the table.

Maybe you could avoid doing that?