Created attachment 161535 [details] GDB backtrace SUMMARY *** NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols. See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports *** STEPS TO REPRODUCE 1. Open a project previously saved 2. During project load Kdenlive crashes with a segfault SOFTWARE/OS VERSIONS Linux/KDE Plasma: Ubuntu 23.04 Lunar MLT: 7.18.0 KDE Plasma Version: ? KDE Frameworks Version: 5.104.0 Qt Version: 5.15.8 ADDITIONAL INFORMATION - Kdenlive installed from Ubuntu PPA - If I open a backup of the project saved with previous Kdenlive version (not sure exactly which version, probably the previous release), it loads OK. - None of the backups saved by 23.08.0 can be opened, resulting in a segfault - GDB reports a SEGFAULT in the thread 1 (the main thread?)
Created attachment 161536 [details] Kdenlive project This is the project that causes the segfault
Can anyone please help resolve that? I'm unable to open the project which is worth many hours of work, essentially lost at the moment...
Have the same problem with new projects - kdenlive crashes (sometime hangs) on startup after some number of open-edit-save-close "cycles" of editing. OS: FreeBSD 13.2-RELEASE-p3 kdenlive-23.08.1 (installed from ports) mlt7-7.18.0 There was not such problem with kdenlive-22.12.0 & mlt7-7.10.0 which I uses previously
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] 0x0000000814ac6d9d in ?? () from /usr/local/lib/mlt-7/libmltavformat.so (gdb) bt #0 0x0000000814ac6d9d in () at /usr/local/lib/mlt-7/libmltavformat.so #1 0x0000000800eebf35 in mlt_frame_get_audio () at /usr/local/lib/libmlt-7.so.7 #2 0x0000000814ad0514 in () at /usr/local/lib/mlt-7/libmltavformat.so #3 0x0000000800eebf35 in mlt_frame_get_audio () at /usr/local/lib/libmlt-7.so.7 #4 0x00000008145d8d9e in () at /usr/local/lib/mlt-7/libmltcore.so #5 0x0000000800eebf35 in mlt_frame_get_audio () at /usr/local/lib/libmlt-7.so.7 #6 0x0000000800ee883d in () at /usr/local/lib/libmlt-7.so.7 #7 0x00000008044dea78 in () at /lib/libthr.so.3 #8 0x0000000000000000 in () (gdb) info threads Id Target Id Frame 1 LWP 115972 of process 40657 0x000000080574c29c in ?? () from /usr/local/lib/libfreetype.so.6 2 LWP 446587 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 3 LWP 446588 of process 40657 "pool-spawner" 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 4 LWP 446589 of process 40657 "gmain" 0x000000080416029a in _poll () from /lib/libc.so.7 5 LWP 446590 of process 40657 "gdbus" 0x000000080416029a in _poll () from /lib/libc.so.7 6 LWP 446591 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 7 LWP 446592 of process 40657 0x00000008041601da in _kevent () from /lib/libc.so.7 9 LWP 446623 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 10 LWP 446624 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 11 LWP 446625 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 12 LWP 446626 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 13 LWP 446627 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 14 LWP 446628 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 15 LWP 446629 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 16 LWP 446630 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 17 LWP 446631 of process 40657 0x000000080416029a in _poll () from /lib/libc.so.7 27 LWP 446642 of process 40657 0x00000008041602ba in _ppoll () from /lib/libc.so.7 28 LWP 446643 of process 40657 0x00000008041602ba in _ppoll () from /lib/libc.so.7 40 LWP 446657 of process 40657 "dconf worker" 0x000000080416029a in _poll () from /lib/libc.so.7 57 LWP 446693 of process 40657 "av:h264:df0" 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 58 LWP 446694 of process 40657 "av:h264:df1" 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 59 LWP 446695 of process 40657 "av:h264:df2" 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 60 LWP 446696 of process 40657 "av:h264:df3" 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 ... 16134 LWP 462821 of process 40657 "av:h264:df15" 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 16135 LWP 462822 of process 40657 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 16136 LWP 462855 of process 40657 "PulseHotplug" 0x00000008041602ba in _ppoll () from /lib/libc.so.7 16137 LWP 462856 of process 40657 0x00000008044dbd2c in ?? () from /lib/libthr.so.3 * 16138 LWP 462857 of process 40657 0x0000000814ac6d9d in ?? () from /usr/local/lib/mlt-7/libmltavformat.so At the same time, I have in my system: kern.maxthread: 1000000 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 release system resourses? I hope above info will help to find problem.
Well in my case it was whopping 7829 threads. Ubuntu doesn't seem to have a parameter for # of threads per process. I tried to increase the VMA count with: echo 600000 | sudo tee /proc/sys/vm/max_map_count But it didn't resolve the issue. Apart from that, the figure of almost 8000 threads seems insane, why does Kdenlive do that?
Also, I see that in your case it's some secondary thread that causes the SIGSEGV, for me it was the thread 1. So it's seemingly a different problem.
Are you able to reproduce this issue with latest version?
(In reply to Maksim K. from comment #3) > Have the same problem with new projects - kdenlive crashes (sometime hangs) > on startup after some number of open-edit-save-close "cycles" of editing. > > OS: FreeBSD 13.2-RELEASE-p3 > > kdenlive-23.08.1 (installed from ports) > mlt7-7.18.0 > > There was not such problem with kdenlive-22.12.0 & mlt7-7.10.0 which I uses > previously The recommended MLT version is 7.20.
It seems it's resolved with the latest kdenlive / mlt 7.20.0. I'm able to open the project again.