[Sugar-devel] Killing activities when memory gets short

[Martin Langhoff]

Hi Tomeu,

in general, I think we are saying the same thing :-)

With one exception -- OOM happens because memory is allocated.
Sugar-shell cannot (and I say should not) try to arbitrage in there.
If we try to do it from sugar-shell, all we can do is poll. If we poll
infrequently, we won't catch them, if we poll frequently, we'll burn
battery, introduce random lags... and still not catch many.

When the shell is in the bg, IMHO it should be as "dormant" as possible.

There are some opportunities for the shell to step-in in a friendly
manner -- activity open, activity switch, I propose that those events
are a natural place; and if a delay happens there is not very
disruptive for users. Between those events checking for low-mem and
seeding the OOM killer to catch runaways, we'll have something.

I don't know of there's a way to ask the OOM killer to run a process
on a lower threshold -- or send a signal to an existing one, that'd
make more sense :-) . If it does, we could have a tight C process
listening there of OOM "warnings" and sending friendly "close now plz"
dbus signals.

cheers,


m
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