Re: Persistent dead rows

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
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