Re: Vacuum wait time problem

On Fri, Feb 13, 2009 at 7:02 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Scott Marlowe <scott.marlowe@gmail.com> writes:
>> On Fri, Feb 13, 2009 at 5:02 PM, Michael Monnerie
>> <michael.monnerie@is.it-management.at> wrote:
>>> vacuum_cost_delay = 0
>>> That was the trick for me. It was set to 250(ms), where it took 5 hours
>>> for a vacuum to run. Now it takes 5-15 minutes.
>
>> Wow!!!  250 ms is HUGE in the scheme of vacuum cost delay.  even 10ms
>> is usually plenty to slow down vacuum enough to keep it out of your
>> way and double to quadruple your vacuum times.
>
> I wonder whether we ought to tighten the allowed range of
> vacuum_cost_delay.  The upper limit is 1000ms at the moment;
> but that's clearly much higher than is useful, and it seems
> to encourage people to pick silly values ...

I agree.  I can't imagine using a number over 50 or so.