On Thu, Sep 25, 2014 at 10:24 AM, Andres Freund <andres@2ndquadrant.com> wrote:
> On 2014-09-25 10:22:47 -0400, Robert Haas wrote:
>> On Thu, Sep 25, 2014 at 10:14 AM, Andres Freund <andres@2ndquadrant.com> wrote:
>> > That leads me to wonder: Have you measured different, lower, number of
>> > buffer mapping locks? 128 locks is, if we'd as we should align them
>> > properly, 8KB of memory. Common L1 cache sizes are around 32k...
>>
>> Amit has some results upthread showing 64 being good, but not as good
>> as 128. I haven't verified that myself, but have no reason to doubt
>> it.
>
> How about you push the spinlock change and I crosscheck the partition
> number on a multi socket x86 machine? Seems worthwile to make sure that
> it doesn't cause problems on x86. I seriously doubt it'll, but ...
OK.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company