Re: [PATCH] PostgreSQL 9.4 mmap(2) performance regression on FreeBSD...

On Thu, Mar 19, 2015 at 12:16 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> On Mon, Oct 13, 2014 at 11:35:18AM -0400, Bruce Momjian wrote:
>> On Mon, Oct 13, 2014 at 05:21:32PM +0200, Andres Freund wrote:
>> > > If we have it, we should improve it, or remove it. We might want to use
>> > > this code for something else in the future, so it should be improved
>> > > where feasible.
>> >
>> > Meh. We don't put in effort into code that doesn't matter just because
>> > it might get used elsewhere some day. By that argument we'd need to
>> > performance optimize a lot of code. And actually, using that code
>> > somewhere else is more of a counter indication than a pro
>> > argument. MAP_NOSYNC isn't a general purpose flag.
>>
>> The key is that this is platform-specific behavior, so if we should use
>> a flag to use it right, we should. You are right that optimizing
>> rarely used code with generic calls isn't a good use of time.
>
> I have adjusted Sean's mmap() options patch to match our C layout and
> plan to apply this to head, as it is from August.

Looks great, thanks for taking care of that.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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