Re: stats collector suddenly causing lots of IO

Josh Kupershmidt <schmiddy(at)gmail(dot)com> writes:
> name | current_setting | source
> ----------------------+-----------------+--------------------
> vacuum_cost_delay | 200ms | configuration file
> vacuum_cost_limit | 100 | configuration file
> vacuum_cost_page_hit | 6 | configuration file
>
> It looks like the default which I have of autovacuum_vacuum_cost_limit
> = -1, which means it's inheriting the vacuum_cost_limit of 100 I had
> set. I'll try bumping vacuum_cost_limit up to 1000 or so.

Actually I think the main problem is that cost_delay value, which is
probably an order of magnitude too high. The way to limit vacuum's
I/O impact on other stuff is to make it take frequent short delays,
not have it run full speed and then sleep a long time. In any case,
your current settings have got it sleeping way too much. Two WEEKS !!!??

regards, tom lane