Re: Proposal of tunable fix for scalability of 8.4

On 3/18/09 4:36 AM, "Gregory Stark" <stark(at)enterprisedb(dot)com> wrote:

>
>
> "Jignesh K. Shah" <J(dot)K(dot)Shah(at)Sun(dot)COM> writes:
>
>> In next couple of weeks I plan to test the patch on a different x64 based
>> system to do a sanity testing on lower number of cores and also try out other
>> workloads ...
>
> I'm actually more interested in the large number of cores but fewer processes
> and lower max_connections. If you set max_connections to 64 and eliminate the
> wait time you should, in theory, be able to get 100% cpu usage. It would be
> very interesting to track down the contention which is preventing that.

My previous calculation in this thread showed that even at 0 wait time, the
client seems to introduce ~3ms wait time overhead on average. So it takes
close to 128 threads in each test to stop the linear scaling since the
average processing time seems to be about ~3ms.
Either that, or the tests actually are running on a system capable of 128
threads.

>
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> Gregory Stark
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