On 06/05/2010 07:19 PM, Niels Mayer wrote: > Potentially, multithread access to shared memory data-structures seems > to be the cause of hard-to-reproduce error messages coming out of > Qt-based apps (see also https://bugs.kde.org/show_bug.cgi?id=240391 ): > > gnulem-109-~/Documents> qtractor > *** glibc detected *** qtractor: corrupted double-linked list: > 0x00000000012ab6a0 *** > ^C > this is most likely one hideous memory corruption bug, runaway memwrite, double or even triple memleak. whatever. do not (ever) rule out my sloppy coding habits. > You may never see these errors until you run these apps on a fast > quad-core machine. For Qtractor -- my hunch of the day -- check for > simultaneous access to the "inputs" and "outputs" configurations; > after loading several projects or activating "track->inputs" > "track->outputs" or the "outputs" and "inputs" buttons in the mixer > (all of which pop up the "Connections" window)... do this a few times > and eventually your midi devices disappear in the gui. You have to go > to the "Connections" window's option-menu and select "(All)" or > reselect the current option in order to refresh the display. > Something's getting "clobbered" in the midi or audio connections > listings each time you load a new .qtr or .qtt file... and this is an > error that recurs more quickly on a fast quad-core than a slower > dual-core. > i do have a quad, where is my primary devel host, intel q8200 though, maybe not the fastest, but still find some of those reported crashes very hard to reproduce. > ... makes me think i was right on track with all my comments about > clojure, garbage-collection, and software transactional management :-) > ... i think i'll need a supercomputer to run "valgrind --tool=helgrind > qtractor" ... > indeed. valgrind may help but it may get you also bored to death even on the fastest of the machines, unless you can reproduce the crashes in a finite, consistent and determined number of steps. i've been there i've done that and still chose to step over and run forward :) cheers -- rncbc aka Rui Nuno Capela rncbc@xxxxxxxxx _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
