Re: Persistent dead rows

From: "Malcolm McLean" <MalcolmM(at)Interpharm(dot)co(dot)za>
To: "Richard Huxton" <dev(at)archonet(dot)com>
Cc: <pgsql-general(at)postgresql(dot)org>
Subject: Re: Persistent dead rows
Date: 2007-02-08 11:20:19
Message-ID: 3823FE6BD7EA064C961B2559C9FED9345DE814@zaidsexch001.interpharm.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Richard Huxton wrote:
> Malcolm McLean wrote:
>> I tested this theory by stopping java applications that were
connected
>> to the database and all other connections that were using
transactions
>> and the full vacuum was still unable to remove the dead rows.
>>
>> What I'm still wondering about, is why the dead row count rises
>> incredibly high, then all of a sudden drops to 0 again when the java
>> apps never stop running.
>
> Are you certain there's no open transaction? Perhaps keep an eye on
> SELECT * FROM pg_stat_activity - there might be something you don't
know
> about.

Okay, I just stopped all java processes again and all pg_stat_activity
returned were IDLE's and no IDLE in transactions. The strange this is
that a cluster command removes the dead rows, and this can only be run
when all the java apps have been stopped.

> If it was the autovacuum interfering, I'd expect a lock failure.

I doubt autovacuum is interfering, I think it is the process that is
clearing the dead rows. If that is the case, then why is only autovacuum
able to clear them and not a manual vacuum.

Malcolm
This information is intended only for the person or entity to which it is addressed and may contain private, confidential, proprietary and/or privileged material and may be subject to confidentiality agreements. If you are not the intended recipient, you are hereby notified that any dissemination, distribution or copying of this e-mail is strictly prohibited. If you have received this e-mail in error, please notify us immediately by return email or telephone +27 12 673-1400 and destroy the original message.

Any review, retransmission, dissemination, or any other use of or taking of any action in reliance upon this information, by persons or entities other than the intended recipient, is prohibited.

The company is neither liable for proper, complete transmission of the information contained in this communication, any delay in its receipt or that the mail is virus-free.

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message jo.dehaes@gmail.com 2007-02-08 11:38:25 Re: DBI-Link 2.0
Previous Message Richard Huxton 2007-02-08 10:41:25 Re: Persistent dead rows