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@enterprisedb.com> wrote:
 

"Jignesh K. Shah" <J.K.Shah@Sun.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 Ask me about EnterpriseDB's PostGIS support!

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