Re: LWLocks in DSM memory

On Tue, Aug 16, 2016 at 5:03 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
> On 2016-08-15 18:15:23 -0400, Robert Haas wrote:
>> On Thu, Aug 11, 2016 at 2:19 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> > Therefore, I plan to commit this patch, removing the #include
>> > <stddef.h> unless someone convinces me we need it, shortly after
>> > development for v10 opens, unless there are objections before then.
>>
>> Hearing no objections, done.
>
> I'd have objected, if I hadn't been on vacation. While I intuitively
> *do* think that the increased wait-list overhead won't be relevant, I
> also know that my intuition has frequently been wrong around the lwlock
> code. This needs some benchmarks on a 4+ socket machine,
> first. Something exercising the slow path obviously. E.g. a pgbench with
> a small number of writers, and a large number of writers.

Amit just pointed out to me that you wrote "a small number of writers,
and a large number of writers". I assume one of those is supposed to
say "readers"? Probably the second one?

--
Robert Haas
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