Re: vacuum taking an unusually long time

On Jul 16, 2008, at 4:40 PM, Mason Hale wrote:

>
>
> On Wed, Jul 16, 2008 at 10:26 AM, Mason Hale <masonhale(at)gmail(dot)com>
> wrote:
> Here's some of the strace output:
>
> select(0, NULL, NULL, NULL, {0, 10000}) = 0 (Timeout)
>
> If I read the 'select(2)' man page correctly, it appears this
> process is waiting indefinitely for a NULL file descriptor.
> That looks pretty stuck to me.

No, it's just sleeping. For 10 milliseconds or so.

>
> Should I kill this autovacuum process via pg_cancel_backend?
> Or is there a better way to "unstick" it?
>
> Any ideas what may have caused it to get into this condition?
>

It looks like "read a page, sleep for 80 milliseconds, repeat".

I'd look at your settings for autovacuum_vacuum_cost_limit /
autovacuum_vacuum_cost_delay, and maybe the contents of pg_autovacuum.

Cheers,
Steve