Re: Keys get stuck

Carlos R. Mafra wrote:
On Thu 13.Mar'08 at 12:28:13 +0100, Mike Galbraith wrote:
[...]
Swap can definitely keep X off the cpu for extended periods,
[...]

So I would like to ask if swap letting X (and everything else
in my experience) out of the cpu for extended periods is
considered normal behaviour, in the sense that nobody is
trying to "fix" it (due to it being considered impossible
to fix)...?
Yes, this is perfectly normal. A heavily swapping machine
will swap out parts of X.

Now, if X has a need for low-latency for keyboard handling,
then the X developers can use mlock to lock
the X keyboard service in memory, and make it a real-time
(or at least high priority) process too. This should
avoid the problem even with extreme swapping and/or
high cpu load.

Sorry for being off-topic, but I run a minimal Window Maker
desktop in a P4 3.0 GHz with 512 MB of RAM (around 140 MB
being used as per 'free'), and trying to load a 380 MB text
file in xjed editor makes my whole desktop quite unfair...
it takes tens of seconds to switch desktop, type things in
the terminal etc.

Seems ou use too much memory then. If xjed
wastes memory (by bringing the entire file into memory
in one go) then you'll get some swapping.

When xjed finishes loading the text file, everything comes
back to "fair" again.

Is there some law in the nature of computers which says
that when swapping everything else waits for swap to finish its business? I hope not :-)
No such law, but there are badly implemented software
around. If xjed is capable of delaying all X events while
loading the file, for example . . .

Helge Hafting
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