https://bugs.kde.org/show_bug.cgi?id=474362
--- Comment #4 from Maksim K. ---
After some investigation I think I found workaround for my case (FreeBSD). I
launched kdenlive in gdb and saw that kdenlive creates a lot of threads (more
then 16000 at the crash/hang time):
Thread 16138 received signal SIGSEGV, Segmentation fault.
Address not mapped to object.
[Switching to LWP 462857 of process 40657]
0x000814ac6d9d in ?? () from /usr/local/lib/mlt-7/libmltavformat.so
(gdb) bt
#0 0x000814ac6d9d in () at /usr/local/lib/mlt-7/libmltavformat.so
#1 0x000800eebf35 in mlt_frame_get_audio () at
/usr/local/lib/libmlt-7.so.7
#2 0x000814ad0514 in () at /usr/local/lib/mlt-7/libmltavformat.so
#3 0x000800eebf35 in mlt_frame_get_audio () at
/usr/local/lib/libmlt-7.so.7
#4 0x0008145d8d9e in () at /usr/local/lib/mlt-7/libmltcore.so
#5 0x000800eebf35 in mlt_frame_get_audio () at
/usr/local/lib/libmlt-7.so.7
#6 0x000800ee883d in () at /usr/local/lib/libmlt-7.so.7
#7 0x0008044dea78 in () at /lib/libthr.so.3
#8 0x in ()
(gdb) info threads
Id Target Id Frame
1LWP 115972 of process 406570x00080574c29c in ?? ()
from /usr/local/lib/libfreetype.so.6
2LWP 446587 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
3LWP 446588 of process 40657 "pool-spawner" 0x0008044dbd2c in ?? ()
from /lib/libthr.so.3
4LWP 446589 of process 40657 "gmain"0x00080416029a in _poll
() from /lib/libc.so.7
5LWP 446590 of process 40657 "gdbus"0x00080416029a in _poll
() from /lib/libc.so.7
6LWP 446591 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
7LWP 446592 of process 406570x0008041601da in _kevent
() from /lib/libc.so.7
9LWP 446623 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
10 LWP 446624 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
11 LWP 446625 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
12 LWP 446626 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
13 LWP 446627 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
14 LWP 446628 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
15 LWP 446629 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
16 LWP 446630 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
17 LWP 446631 of process 406570x00080416029a in _poll
() from /lib/libc.so.7
27 LWP 446642 of process 406570x0008041602ba in _ppoll
() from /lib/libc.so.7
28 LWP 446643 of process 406570x0008041602ba in _ppoll
() from /lib/libc.so.7
40 LWP 446657 of process 40657 "dconf worker" 0x00080416029a in _poll
() from /lib/libc.so.7
57 LWP 446693 of process 40657 "av:h264:df0" 0x0008044dbd2c in ?? ()
from /lib/libthr.so.3
58 LWP 446694 of process 40657 "av:h264:df1" 0x0008044dbd2c in ?? ()
from /lib/libthr.so.3
59 LWP 446695 of process 40657 "av:h264:df2" 0x0008044dbd2c in ?? ()
from /lib/libthr.so.3
60 LWP 446696 of process 40657 "av:h264:df3" 0x0008044dbd2c in ?? ()
from /lib/libthr.so.3
...
16134 LWP 462821 of process 40657 "av:h264:df15" 0x0008044dbd2c in ?? ()
from /lib/libthr.so.3
16135 LWP 462822 of process 406570x0008044dbd2c in ?? ()
from /lib/libthr.so.3
16136 LWP 462855 of process 40657 "PulseHotplug" 0x0008041602ba in _ppoll
() from /lib/libc.so.7
16137 LWP 462856 of process 406570x0008044dbd2c in ?? ()
from /lib/libthr.so.3
* 16138 LWP 462857 of process 406570x000814ac6d9d in ?? ()
from /usr/local/lib/mlt-7/libmltavformat.so
At the same time, I have in my system:
kern.maxthread: 100
kern.threads.max_threads_hits: 7135
kern.threads.max_threads_per_proc: 2048
max_threads_hits is just a count, as I understand, which show how many times we
reached threads limit. So I increased max_threads_per_proc value iterately
(with reboot) and found that max_threads_hits decreases on every iteratition
(after launch kdenlive) and become 0 when max_threads_per_proc reached 16384
and kdelive launch my project corretly without crash. So, now I set
max_threads_per_proc=32768 and it seems that this resolves my problem
But I beleave that "low" number of threads in system settings is not root cause
of the problem. This is because, my previous project was large: ~1700 clips vs
carrent has ~1200, but I had no problem with previous version of Kdenlive
(22.12.0). Also, it is a question - is application really need create so many
threads? And is this corret behavior to crahs, not just waiting to
