On Tue, Nov 22, 2022 at 6:15 PM Mike Dewhirst <mi...@dewhirst.com.au> wrote:
> Can anyone suggest some mpm_event.conf settings for a lightly loaded
> DigitalOcean Ubuntu 2022.04 LTS droplet with 8GB of RAM and a "dedicated
> CPU"?
>
> I just had to restart Apache which crashed around 22:22 UTC. There is 8Mb
> of the above error in the log.
>
> This is the plain Apache2 error.log rather than the named website error
> log which only shows expected errors such as reCaptcha errors.
>
> It seems to have started filling the scoreboard 24 minutes after
> logrotate. The first ten log entries after logrotate are ...
>
> [Tue Nov 22 00:00:01.934987 2022] [mpm_event:notice] [pid 49892:tid
> 140450581641088] AH00489: Apache/2.4.52 (Ubuntu) OpenSSL/3.0.2
> mod_wsgi/4.9.0 Python/3.10 configured -- resuming normal operations
> [Tue Nov 22 00:00:01.935032 2022] [core:notice] [pid 49892:tid
> 140450581641088] AH00094: Command line: '/usr/sbin/apache2'
> [Tue Nov 22 00:20:13.411015 2022] [mpm_event:notice] [pid 49892:tid
> 140450581641088] AH00493: SIGUSR1 received. Doing graceful restart
> [Tue Nov 22 00:20:13.514771 2022] [mpm_event:notice] [pid 49892:tid
> 140450581641088] AH00489: Apache/2.4.52 (Ubuntu) OpenSSL/3.0.2
> mod_wsgi/4.9.0 Python/3.10 configured -- resuming normal operations
> [Tue Nov 22 00:20:13.514804 2022] [core:notice] [pid 49892:tid
> 140450581641088] AH00094: Command line: '/usr/sbin/apache2'
> [Tue Nov 22 00:23:57.862865 2022] [mpm_event:notice] [pid 49892:tid
> 140450581641088] AH00493: SIGUSR1 received. Doing graceful restart
> [Tue Nov 22 00:23:57.937161 2022] [mpm_event:notice] [pid 49892:tid
> 140450581641088] AH00489: Apache/2.4.52 (Ubuntu) OpenSSL/3.0.2
> mod_wsgi/4.9.0 Python/3.10 configured -- resuming normal operations
> [Tue Nov 22 00:23:57.937192 2022] [core:notice] [pid 49892:tid
> 140450581641088] AH00094: Command line: '/usr/sbin/apache2'
> [Tue Nov 22 00:23:59.938800 2022] [mpm_event:error] [pid 49892:tid
> 140450581641088] AH03490: scoreboard is full, not at
> MaxRequestWorkers.Increase ServerLimit.
> [Tue Nov 22 00:24:00.939954 2022] [mpm_event:error] [pid 49892:tid
> 140450581641088] AH03490: scoreboard is full, not at
> MaxRequestWorkers.Increase ServerLimit.
>
With event, ServerLimit should be larger than
MaxRequestWorkers/ThreadsPerChild not equal to it. It only matters when
processes exit and are replaced.
This allows slow to exit processes to be managed alongside their
replacement processes.
...
<IfModule mpm_event_module>
> ServerLimit 16
>
StartServers 16
> MinSpareThreads 400
> MaxSpareThreads 250
> ThreadLimit 64
> ThreadsPerChild 50
> AsyncRequestWorkerFactor 2
> MaxRequestWorkers 800
> MaxConnectionsPerChild 0
> </IfModule>
>
I would start with ServerLimit 24 or 32. Nothing has to change along with
it.
