> On 1 Jun 2021, at 05:26, Marc Shapiro via Dng <dng@???> wrote:
>
> I received this e-mail yesterday, and again today:
>
> -----------------------------------------
> exim paniclog /var/log/exim4/paniclog on quixote.home has non-zero size, mail system might be broken. The last 10 lines are quoted below.
>
> 2021-05-29 19:35:47 daemon: fork of queue-runner process failed: Cannot allocate memory
> -----------------------------------------
>
> I use Thunderbird for all non-local mail.
> I am only using exim for local mail.
> The only mail that I receive locally is a weekly e-mail from a cron job that I have set up to do backups, and I did receive that e-mail yesterday, along with the above e-mail.
>
> I'm not familiar with the workings of exim, or any MTA, so I don't really know what the error message means, other than that there was some memory issue. The one clue that I have is that something (I am fairly sure that it was a Firefox tab) completely locked my system on Saturday night. Everything started slowing down. Mousing became erratic. Then everything completely stopped. I couldn't even switch to a terminal where I could kill Firefox. I finally had to simply power down the system. (How I hate doing that!) Then I rebooted, did a controlled shutdown and rebooted, again. After that, everything seems to be running just fine.
>
> Is that likely the cause of the above message? If so, is deleting the paniclog the proper way to stop receiving these e-mails?
>
> Marc
>

Next time, before just powering down the system, you should try the Magic SysRq keyboard shortcuts to see if the kernel is still responding.

https://www.kernel.org/doc/html/latest/admin-guide/sysrq.html

I like to follow the example used on the Wikipedia page which lists the Alt+SysRq+REISUB keys for doing a safer reboot than simply just hitting the physical power button. I try to leave a few of seconds at least in between key presses, to give time for each command to process completely.

https://en.m.wikipedia.org/wiki/Magic_SysRq_key

--
Tom