Idle processes chewing up CPU?

I recently migrated from MSSQL2000 to Postgres 8.3 for Windows, and overall
it's running great.

Using the Process Explorer tool, I've noticed that a child postgres.exe is
chewing up 25% of the CPU usage each (we have two dual-core CPUs, presumably
it's chewing up one core). Using SELECT * FROM pg_stat_activity, I located
the process id (#3884), and it showed:

datid

datname

procpid

usesysid

usename

current_query

waiting

xact_start

query_start

backend_start

client_addr

client_port

11511

postgres

3884

16395

Brendan.Hill

<IDLE>

f

2009-07-28 13:54:50.055+10

2009-07-28 13:54:44.508+10

###

3353

No processes are waiting. This was taken at 2:19pm, so it had been running
for about 25 minutes. This has happened before - we had two runaway
processes, and they each chewed up 25% of the CPU for several weeks, before
we forcefully shut them down. We had to forcefully shut them down before we
could restart the Postgres service.

Other requests are being served, however we've had reports of slowness
(which sparked off the initial search). I can't confirm this runaway process
is the source of it, but it shouldn't be happening either way. I've killed
it just in case.

Any thoughts on what is causing this, or how I could diagnose the problem
further?

Regards,

Brendan Hill

Chief Information Officer

Jims Group Pty Ltd

48 Edinburgh Rd

Mooroolbark VIC 3138

www.jims.net

For all Jims IT enquiries: infotech(at)jims(dot)net

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