[pulseaudio-discuss] Some issues with 0.9.16.

[Colin Guthrie]

'Twas brillig, and Lennart Poettering at 28/08/09 15:39 did gyre and gimble:
>> 3) I'm also seeing quite regularly a deadlock in pulse. This one is  
>> quite serious as it obviously freezes the display of most libcanberra  
>> apps :s See attached pulse-deadlock.txt
> 
>> #0  0x00007f706ab57ea7 in mlock () from /lib64/libc.so.6
>> #1  0x00007f706e2ef0d2 in pa_will_need (p=0xc300c300c300c3, l=<value optimized out>) at pulsecore/core-util.c:2140
>> #2  0x00007f706e2fdbea in pa_memchunk_will_need (c=0x23cf0f8) at pulsecore/memchunk.c:88
>> #3  0x00007f706e2fccb9 in pa_memblockq_willneed (bq=<value optimized out>) at pulsecore/memblockq.c:914
> 
> [...]
> 
>>   4 Thread 0x7f706a86b910 (LWP 9012)  0x00007f706ab51a47 in ppoll () from /lib64/libc.so.6
>>   3 Thread 0x7f70648f4910 (LWP 9016)  0x00007f706ab51a47 in ppoll () from /lib64/libc.so.6
>>   2 Thread 0x7f70640f3910 (LWP 9149)  0x00007f706ab51a47 in ppoll () from /lib64/libc.so.6
>> * 1 Thread 0x7f706ebba6f0 (LWP 8899)  0x00007f706ab57ea7 in mlock () from /lib64/libc.so.6
> 
> The IO threads are hanging in ppoll(), and are hence not
> deadlocked. The main thread hangs in mlock(). Which is a fucntion that
> locks memory into RAM. We use it as a dirty hack for making sure
> cached samples are swapped back into RAM before we ask the IO threads
> to play them. Normally, mlock() should just swap things in and lock
> them. We then immediately call munlock(). If this freezes for you then
> there is something really wrong with your kernel. I have not seen this
> issue before. 

This seems be be behaving better with a new kernel... not had the 
problem again so far. I think the rc8 had some messed up inotify stuff 
which may explain it.


Col

-- 

Colin Guthrie
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