On Tue, 2004-10-26 at 23:44, Tom Lane wrote:
> In previous releases it was possible to observe whether an automatic
> checkpoint was in progress by looking to see if there was a postmaster
> child process doing one. In 8.0 this will not work because the bgwriter
> is always there. I am thinking that for tasks such as performance
> debugging it would be a good idea if the bgwriter could emit postmaster
> log messages at start and end of a checkpoint. However, this should
> probably not happen at the default LOG level since it would clutter the
> logs with perfectly routine messages. Any opinions about what elog
> level to use for this?
>
Yes, please.
The end message should say:
- checkpoint duration
- blocks written
- number of xlog files recycled
The last one can then replace the multiple recycled file messages, or at
least push them down to DEBUG2.
For now, DEBUG1. Longer term, we need to discuss a "performance log" or
some place to put regularly collected performance statistics, rather
than site specific ones.
--
Best Regards, Simon Riggs