From: Josh Berkus <josh@agliodbs.com>
Reply-To: josh@agliodbs.com
Organization: Aglio Database Solutions
To: pgsql-performance@postgresql.org
Subject: Re: large number of connected connections to postgres database (v8.0)
Date: Fri, 20 Jul 2007 16:28:27 -0700
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Cc: Fei Liu <fei.liu@aepnetworks.com>
References: <469D0F99.1030002@aepnetworks.com>
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Fei Liu,

> It appears my multi-thread application (100 connections every 5 seconds)
> is stalled when working with postgresql database server. I have limited
> number of connections in my connection pool to postgresql to 20. At the
> begining, connection is allocated and released from connection pool as
> postgres serves data request. The pool can recover from exhaustion. But
> very quickly (after about 400 client requests), it seems postgres server
> stops serving and connection to postgres server is not released any more
> resulting a resource exhausting for clients.

This sounds more like a problem with your connection pool.  Unless 
PostgreSQL is slowing down due to CPU/RAM/I/O saturation?

In any case, I doubt the problem is too many connections, or you'd just get 
an error message ...

-- 
--Josh

Josh Berkus
PostgreSQL @ Sun
San Francisco