Few weeks ago tested a customer application on 16 cores with Oracle:
  - 20,000 sessions in total
  - 70,000 queries/sec
without any problem on a mid-range Sun box + Solaris 10..
Rgds,
-Dimitri
On 6/3/09, Kevin Grittner <[email protected]> wrote:
> James Mansion <[email protected]> wrote:
>
>> I'm sure most of us evaluating Postgres from a background in Sybase
>> or SQLServer would regard 5000 connections as no big deal.
>
> Sure, but the architecture of those products is based around all the
> work being done by "engines" which try to establish affinity to
> different CPUs, and loop through the various tasks to be done.  You
> don't get a context switch storm because you normally have the number
> of engines set at or below the number of CPUs.  The down side is that
> they spend a lot of time spinning around queue access to see if
> anything has become available to do -- which causes them not to play
> nice with other processes on the same box.
>
> If you do connection pooling and queue requests, you get the best of
> both worlds.  If that could be built into PostgreSQL, it would
> probably reduce the number of posts requesting support for bad
> configurations, and help with benchmarks which don't use proper
> connection pooling for the product; but it would actually not add any
> capability which isn't there if you do your homework....
>
> -Kevin
>
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