bug#13103: 24.3.50; Trunk --with-ns eats 100% CPU

[Jan Djärv]

Hello.

7 dec 2012 kl. 07:21 skrev Eli Zaretskii <eliz@gnu.org>:

>> From:     Didier Verna <didier@didierverna.net>
>> Cc: 13103@debbugs.gnu.org
>> Date: Thu, 06 Dec 2012 22:24:11 +0100
>> 
>>  Here's the result of gdb's 'where' when I kill -TSTP the Emacs.app
>>  process, after attaching GDB to it. Not sure that's very useful. Also,
>>  I should point out that Emacs itself does NOT hang or become
>>  unresponsive. It works like a charm. It's just that the CPU usage goes
>>  way up.
>> 
>> 
>> 
>> #0  0x00007fff838dfd7a in mach_msg_trap ()
>> #1  0x00007fff838e0444 in mach_msg ()
>> #2  0x00007fff89580902 in __CFRunLoopRun ()
>> #3  0x00007fff8957fd8f in CFRunLoopRunSpecific ()
>> #4  0x00007fff809507ee in RunCurrentEventLoopInMode ()
>> #5  0x00007fff809505f3 in ReceiveNextEventCommon ()
>> #6  0x00007fff809504ac in BlockUntilNextEventMatchingListInMode ()
>> #7  0x00007fff83ae4eb2 in _DPSNextEvent ()
>> #8  0x00007fff83ae4801 in -[NSApplication 
>> nextEventMatchingMask:untilDate:inMode:dequeue:] ()
>> #9  0x00007fff83aaa68f in -[NSApplication run] ()
>> #10 0x0000000100191d95 in ns_select (nfds=1, readfds=0x7fff5fbfa290, 
>> writefds=0x7fff5fbfa210, exceptfds=<value temporarily unavailable, due to 
>> optimizations>, timeout=0x7fff5fbfa330, sigmask=<value temporarily 
>> unavailable, due to optimizations>) at 
>> /usr/local/src/emacs/trunk/src/nsterm.m:3537
>> #11 0x000000010015dfad in wait_reading_process_output
>> #(time_limit=<value temporarily unavailable, due to optimizations>,
>> #nsecs=0, read_kbd                  
> 
> Next step is to see which file descriptor is being watched here.
> (There's only one because nfds = 1.)
> 
> Also, I suggest to do this experiment several times, to make sure that
> this is indeed related to the call to ns_select.

If Emacs is started with -Q there shouldn't be any fds.  So either something is 
done after starting Emacs or some plugin/extension is doing something.

Print out the readfds, and figure out what the fd is.  Then use lsof to see 
what that fd really is.

        Jan D.