Re: HEAD seems to generate larger WAL regarding GIN index

Fujii Masao escribió:
> On Sun, Mar 16, 2014 at 7:15 AM, Alexander Korotkov
> <aekorotkov(at)gmail(dot)com> wrote:

> >> That could be optimized, but I figured we can live with it, thanks to the
> >> fastupdate feature. Fastupdate allows amortizing that cost over several
> >> insertions. But of course, you explicitly disabled that...
> >
> > Let me know if you want me to write patch addressing this issue.
>
> Yeah, I really want you to address this problem! That's definitely useful
> for every users disabling FASTUPDATE option for some reasons.

Users that disable FASTUPDATE, in my experience, do so because their
stock work_mem is way too high and GIN searches become too slow due to
having to scan too large a list. I think it might make sense to invest
a modest amount of time in getting FASTUPDATE to be sized completely
differently from today -- perhaps base it on a hardcoded factor of
BLCKSZ, rather than work_mem. Or, if we really need to make it
configurable, then let it have its own parameter.

--
Álvaro Herrera http://www.2ndQuadrant.com/
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