Re: Should we increase the default vacuum_cost_limit?

On 3/6/19 12:10 AM, David Rowley wrote:
> Thanks for chipping in on this.
>
> On Wed, 6 Mar 2019 at 01:53, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com> wrote:
>> But on the other hand it feels a bit weird that we increase this one
>> value and leave all the other (also very conservative) defaults alone.
>
> Which others did you have in mind? Like work_mem, shared_buffers? If
> so, I mentioned in the initial post that I don't see vacuum_cost_limit
> as in the same category as those. It's not like PostgreSQL won't
> start on a tiny server if vacuum_cost_limit is too high, but you will
> have issues with too big a shared_buffers, for example. I think if
> we insist that this patch is a review of all the "how big is your
> server" GUCs then that's raising the bar significantly and
> unnecessarily for what I'm proposing here.
>

On second thought, I think you're right. It's still true that you need
to bump up various other GUCs on reasonably current hardware, but it's
true vacuum_cost_limit is special enough to increase it separately.

so +1 (I see Andrew already pushed it, but anyway ...)

--
Tomas Vondra http://www.2ndQuadrant.com
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