Re: Perfomance degradation 9.3 (vs 9.2) for FreeBSD

On 2014-04-21 15:47:31 -0400, Stephen Frost wrote:
> That's certainly unfortunate.  For my 2c, I'd recommend that you write a
> minimal implementation that allows you to test just the sysv-vs-mmap
> case (which could certainly take an option, to avoid having to
> recompile during testing), or even ask if anyone here already has;

I don't think that's something all that easily testable in
isolation. The behaviour here is heavily related to concurrency.

> I
> wouldn't be at all surprised if both Robert and Francois did exactly
> that already, nor would I be surprised if someone volunteered to write
> such a small C utility for you, if it meant that this issue would be
> fixed in FreeBSD that much sooner.

I don't know, but the patch for a guc would be < 10 lines. I think I'd
start with that.

Greetings,

Andres Freund

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