Re: Should we increase the default vacuum_cost_limit?

On 2/25/19 8:38 AM, David Rowley wrote:
> On Tue, 26 Feb 2019 at 02:06, Joe Conway <mail(at)joeconway(dot)com> wrote:
>> On 2/25/19 1:17 AM, Peter Geoghegan wrote:
>>> On Sun, Feb 24, 2019 at 9:42 PM David Rowley
>>> <david(dot)rowley(at)2ndquadrant(dot)com> wrote:
>>>> The current default vacuum_cost_limit of 200 seems to be 15 years old
>>>> and was added in f425b605f4e.
>>>>
>>>> Any supporters for raising the default?
>>> I also think that the current default limit is far too conservative.
>> I agree entirely. In my experience you are usually much better off if
>> vacuum finishes quickly. Personally I think our default scale factors
>> are horrible too, especially when there are tables with large numbers of
>> rows.
> Agreed that the scale factors are not perfect, but I don't think
> changing them is as quite a no-brainer as the vacuum_cost_limit, so
> the attached patch just does the vacuum_cost_limit.
>
> I decided to do the times by 10 option that I had mentioned.... Ensue
> debate about that...
>
> I'll add this to the March commitfest and set the target version as PG12.
>

This patch is tiny, seems perfectly reasonable, and has plenty of
support. I'm going to commit it shortly unless there are last minute
objections.

cheers

andrew

--
Andrew Dunstan https://www.2ndQuadrant.com
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