Re: Proposal of tunable fix for scalability of 8.4

"Jignesh K. Shah" <J(dot)K(dot)Shah(at)Sun(dot)COM> writes:

> Scott Carey wrote:
>> On 3/12/09 11:37 AM, "Jignesh K. Shah" <J(dot)K(dot)Shah(at)Sun(dot)COM> wrote:
>>
>> In general, I suggest that it is useful to run tests with a few different
>> types of pacing. Zero delay pacing will not have realistic number of
>> connections, but will expose bottlenecks that are universal, and less
>> controversial
>
> I think I have done that before so I can do that again by running the users at
> 0 think time which will represent a "Connection pool" which is highly utilized"
> and test how big the connection pool can be before the throughput tanks.. This
> can be useful for App Servers which sets up connections pools of their own
> talking with PostgreSQL.

Keep in mind when you do this that it's not interesting to test a number of
connections much larger than the number of processors you have. Once the
system reaches 100% cpu usage it would be a misconfigured connection pooler
that kept more than that number of connections open.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
Ask me about EnterpriseDB's PostGIS support!