bug#15156: 24.3; !MEM FULL!

[Eli Zaretskii <eliz@gnu.org>]

> From: "Sebastien Vauban" <sva-news@mygooglest.com>
> Date: Sat, 24 Aug 2013 15:57:42 +0200
> Cc: 15156@debbugs.gnu.org
> 
> >>> Turn off flyspell and see whether it still happens?
> >>
> >> Quite complex,
> 
> Eli wrote:
> > So you are saying that some (most?) of your sessions don't exhibit
> > this problem at all?  Earlier, you said that the problematic sessions
> > are only several hours old, and this "once a week" seems to contradict
> > that, because if the memory footprint grows so much in just a few
> > hours, you should see these problems in almost every session.  What am
> > I missing?
> 
> I said that:
> 
> - MEM FULL problem doesn't occur in Emacs sessions of tens of hours long, as I
>   generally restart Emacs at least once a day.

No, you said:

> > And how long was that session up and running, before that happened?
> > (You can use the emacs-uptime command to answer the last question.)
> 
> 15 hours, 14 minutes, 3 seconds
> 
> But you must substract the night... So, in fact, something like 6 to 8 hours.

So, if you each day have a 15-hour long session, you should have this
problem almost every day.  If you don't, that means when the problem
happens you do something relatively extraordinary.  Maybe you could
try figuring out what that could be.

> In my head, it has never been clear that Emacs would be constantly growing, at
> all times (unconditionally), and that if I wait long enough, I won't escape
> the MEM FULL problem.

It shouldn't grow constantly.  Here's what I see on my system:

  Name                Pid Pri Thd  Hnd   Priv        CPU Time    Elapsed Time 
  emacs              4388   8   6  140 195124     1:32:49.906   238:09:46.822

This session runs for more than 9 days.

> [1] Every 10s, I log "pslist emacs". I sometimes had two Emacs instances
>     running in parallel.

The memory footprint grows almost monotonically, and too fast, IMO.
But it never goes anywhere near the 1.6GB mark, so I'm not sure we see
here something important.  It would be interesting to see the memory
history of a session which does get to MEM FULL.

> I guess that "time gaps" such as:
> 
> emacs              2440   8   6  236  67836     0:01:44.187     0:54:30.142
> emacs              2440   8   6  236  67836     0:01:44.234     1:14:33.897
> 
> indicate that I closed the lid of my laptop, hibernating it for 20 minutes?

I don't think it's hibernation, unless pslist has some tricks up its
sleeve: when the machine hibernates, the elapsed time of all processes
stops advancing.