Обсуждение: BUG #1531: rotated log truncation broken

The following bug has been logged online:

Bug reference:      1531
Logged by:          Markus Bertheau
Email address:      twanger@bluetwanger.de
PostgreSQL version: 8.0.1
Operating system:   Linux FC3
Description:        rotated log truncation broken
Details:

The log truncation is broken for me. It works as advertised, and I follow
the argumentation behind it, but for my scenario it is not working:

I use the computer only in work hours; it's shut down in the night.

I use the standard log rotation thing that is set up in the RPM distributed
by the PGDG.

My logs are not truncated because postgres was not running when the time
based rotation occurs.

So my logs are growing and growing :/

I see that if you would "blindly" truncate time-based rotated logs on server
start, that would be counter productive, because you may want to have the
logs of the full day.

So what about a timestamp at server shutdown, and at server start you handle
the log rotation thing as if pg ran all the time, just that nothing has
happend since that timestamp? That way the truncation would only indeed take
place if the rotation time period was over.

If that doesn't work out for some reason, I think another solution is needed
nevertheless.

Thanks for your consideration

Markus Bertheau

Markus Bertheau wrote:
> The following bug has been logged online:
>
> Bug reference:      1531
> Logged by:          Markus Bertheau
> Email address:      twanger@bluetwanger.de
> PostgreSQL version: 8.0.1
> Operating system:   Linux FC3
> Description:        rotated log truncation broken
> Details:
>
> The log truncation is broken for me. It works as advertised, and I follow
> the argumentation behind it, but for my scenario it is not working:
>
> I use the computer only in work hours; it's shut down in the night.
>
> I use the standard log rotation thing that is set up in the RPM distributed
> by the PGDG.
>
> My logs are not truncated because postgres was not running when the time
> based rotation occurs.

You probably want to look at the "anacron" package - should be installed
by default. Designed for just this sort of thing.

You should find if you log to syslog it's already rotating those files.

--
   Richard Huxton
   Archonet Ltd

"Markus Bertheau" <twanger@bluetwanger.de> writes:
> The log truncation is broken for me. It works as advertised, and I follow
> the argumentation behind it, but for my scenario it is not working:

> I use the computer only in work hours; it's shut down in the night.

> I use the standard log rotation thing that is set up in the RPM distributed
> by the PGDG.

> My logs are not truncated because postgres was not running when the time
> based rotation occurs.

An easy answer is to change the log filename pattern so that rotation
happens hourly instead of daily.  The setup created by the RPM is only
a useful default; it's not intended to be the perfect answer for everyone.

            regards, tom lane