Zombie processes

From: "Peterson, Bjorn" <Bjorn(dot)Peterson(at)pearson(dot)com>
To: pgsql-general(at)postgresql(dot)org
Subject: Zombie processes
Date: 2005-03-29 15:04:56
Message-ID: 42E7C401A4CBCD49829BB53DDD538BA4020DE869@chmpgexgmail3.ic.ncs.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

I'm running out of ideas for the following problem:

I have a moderately complex query as follows-

SELECT t.term_id, a.user_id, a.time_slot, a.status,

SUM(CASE WHEN a.date>=t.start_date THEN 1 ELSE 0 END), COUNT(a. date)

FROM "Table1" a, "Table2" t, "Table2" ytd, "Table3" cu, "Table4" c, "Table5"
co, "Table6" s

WHERE a.type=1 AND a.status IN(1,2,3,4) AND a.date>=ytd.start_date AND
a.date<=t.end_date AND

a.date<=now() AND a.user_id=cu.user_id AND a.time_slot=cu.course_id AND
cu.course_id=c.course_id AND co.course_offered_id=c.course_offered_id

AND co.school_id=s.school_id AND s.district_id=2 AND
ytd.term_id=t.top_term_id GROUP BY a.user_id, a.time_slot, t.term_id,
a.status

ORDER BY a.user_id, a.time_slot, t.term_id, a.status

I am running Postgres 8.0.1 on a Windows 2000 server as a service, and the
query returns appropriate values after about 30 seconds when executed from a
psql console. However, when running this query from a Java application on
the same machine through the postgres JDBC driver, the Java app hangs on
st.executeQuery(). The query shows up in pg_stat_activity for about 3
minutes then goes away, but the process referenced by the pg_stat_activity
remains active and consumes 50% of the CPU resources indefinitely until I
kill it off. I let it run for over an hour yesterday. I can reproduce this
every time I run this query.

Any ideas?

Bjorn Peterson

Software Engineer

Pearson School Technologies

Bloomington, MN

Bjorn(dot)Peterson(at)pearson(dot)com

****************************************************************************
This email may contain confidential material.
If you were not an intended recipient,
Please notify the sender and delete all copies.
We may monitor email to and from our network.
****************************************************************************

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Alex Adriaanse 2005-03-29 15:34:39 Re: Tracking row updates - race condition
Previous Message dharana 2005-03-29 14:56:24 Unable to restore table oids from pg_dump