[kwlug-disc] Service resource management: i.e. Mailman3 vs Mailman2

[Ronald Barnes]

Khalid Baheyeldin wrote on 2025-01-30 16:35:

> Just curious ... Did you try other tools, e.g. top, to see the memory 
> usage per python process?

I used the `free` command with mailman running then with it stopped.

Not very precise breakdown (I'm not keen on `free`).  But it clearly 
showed a dramatic difference (I forget the numbers, a couple / few 
hundred MB for MM2 vs ~1.4 GB for MM3?)


I just had a look at top, htop, and btop.

The results were sub-optimal. Filtering for "postgres" also shows `sudo 
-u postgres psql ...` and filtering on "mailman" doesn't give a summary, 
nor do I know if I have all processes showing (i.e. in systemctl output 
there's a process called `sh` running).


It seems summing the processes memory usage is a manual task that way too.

Maybe I'm there are some features that I'm unaware of?




> I agree that they have to address their own need first and foremost.
> Perhaps others who run smaller lists can the advice/contribute on how to 
> pare down memory usage.
> 
> One obvious way to do this is modularization, and configurability.
> Examples, number of worker processes (e.g. how Apache, Nginx or PHP-FPM 
> handles it: number of processes to start with, maximum number, and 
> number of hot spares), or features (fancy user interface yes/no).

I do wish it were more like that, but with the Apache / Nginx example, 
each process does the same thing, so it scales - with Mailman, each 
Python is doing a separate task.



> But because this is obvious, perhaps it is already there, or tried and 
> didn't work for some reason.
> 
> In any case, it doesn't hurt to write follow ups for the issues on 
> Gitlab, and send the info in your original message. Maybe if enough 
> people report this as an issue, a solution would be found.

I might do that. I've now got some evidence I could share there.


I've got MM3 testing disabled at the moment and might just shut down MM2 
and quit hosting mailing lists.

Until such a time as someone wants to pay for the resources they require...