Re: [bug fix] Suppress "autovacuum: found orphan temp table" message

Hi,

On 2014-07-18 23:38:09 +0900, MauMau wrote:
> My customer reported a problem that the following message is output too
> often.
>
> LOG: autovacuum: found orphan temp table "pg_temp_838"."some_table" in
> database "some_db"
> LOG: autovacuum: found orphan temp table "pg_temp_902"."some_table" in
> database "some_db"

So they had server crashes of some form before - otherwise they
shouldn't see this because during ordinary shutdown the schema will have
been dropped. C.f. RemoveTempRelationsCallback().

> 1. Why and when are these messages are output? Do we have to do
> something?

Yes, you should investigate how the situation came to be.

> 2. Won't they use up disk space?

Yes.

> 3. Doesn't the output processing of these messages or its cause affect
> performance? We happen to be facing a performance problem, the cause of
> which we haven't found yet.

Meh. If that's the bottleneck you've bigger problems.

> So, I propose a simple fix to change the LOG level to DEBUG1. I don't know
> which of DEBUG1-DEBUG5 is appropriate, and any level is OK. Could you
> include this in 9.2.9?

Surely that's the wrong end to tackle this from. Hiding actual problems
is a seriously bad idea.

It'd be nice if we had infrastructure to do this at startup, but we
don't...

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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