Re: Proposal of tunable fix for scalability of 8.4

On 03/18/09 17:16, Scott Carey wrote:
> 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.
>
>

Nope 64 threads for sure .. Verified it number of times ..

-Jignesh

>> --
>> Gregory Stark
>> EnterpriseDB http://www.enterprisedb.com
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