Re: Emacs in CVS plus GTK patches hogs CPU

[Simon Josefsson <jas@extundo.com>]

"Jan D." <jan.h.d@swipnet.se> writes:

>> I've been using the #2 GTK patch for several days with some heavy use,
>> and this is my first problem.  I'm not positive it is GTK related.
>> 
>> Emacs is unresponsive to C-g and consumes all CPU.  Attaching with gdb
>> and breaking alternatively generates two different backtraces (see
>> below).  At the time I was reading mail from a IMAP group using Gnus
>> (i.e., likely both network activity and keyboard activity).
>> 
>> I'll keep the process running if someone has any ideas what to
>> investigate.
>
> I have Motif and GTK versions running side by side, the GTK version
> actually takes *less* CPU for me.

Yes, normally I have no problems, but this emacs instance is
completely lost in a busy wait.  No redisplay, C-g doesn't work.

> Can you strace or truss the Emacs process to see if is in some sort of busy
> wait?  A very short timeout perhaps?

Yes, it is a busy wait:

...
kill(17005, SIGIO)                      = 0
gettimeofday({1042058269, 284790}, NULL) = 0
select(8, [3 7], NULL, NULL, {0, 451252}) = 1 (in [7], left {0, 453096})
gettimeofday({1042058269, 284976}, NULL) = 0
getpid()                                = 17005
kill(17005, SIGIO)                      = 0
gettimeofday({1042058269, 285079}, NULL) = 0
select(8, [3 7], NULL, NULL, {0, 450963}) = 1 (in [7], left {0, 451143})
gettimeofday({1042058269, 285265}, NULL) = 0
getpid()                                = 17005
kill(17005, SIGIO)                      = 0
gettimeofday({1042058269, 285368}, NULL) = 0
select(8, [3 7], NULL, NULL, {0, 450674}) = 1 (in [7], left {0, 451143})
gettimeofday({1042058269, 285554}, NULL) = 0
...

This doesn't look GTK related, but rather network process related,
though.  Hm.  17005 is the pid of the emacs process itself.  Does GTK
catch SIGIO or something?