Re: Redesigning checkpoint_segments

* Robert Haas (robertmhaas(at)gmail(dot)com) wrote:
> On Mon, Mar 2, 2015 at 6:43 AM, Heikki Linnakangas <hlinnaka(at)iki(dot)fi> wrote:
> > On 02/26/2015 01:32 AM, Josh Berkus wrote:
> >> But ... I thought we were going to raise the default for max_wal_size to
> >> something much higher, like 1GB? That's what was discussed on this
> >> thread.
> >
> > No conclusion was reached on that. Me and some others were against raising
> > the default, while others were for it.
>
> I guess that's a fair summary of the discussion, but I still think
> it's the wrong conclusion. Right now, you can't get reasonable write
> performance with PostgreSQL even on tiny databases (a few GB) without
> increasing that setting by an order of magnitude. It seems an awful
> shame to go to all the work to mitigate the downsides of setting a
> large checkpoint_segments and then still ship a tiny default setting.
> I've got to believe that the number of people who think 128MB of WAL
> is tolerable but 512MB or 1GB is excessive is almost nobody. Disk
> sizes these days are measured in TB.

+1. I thought the conclusion had actually been in favor of the change,
though there had been voices for and against.

Thanks,

Stephen