Le 03/11/2015 18:13, LyX Ticket Tracker a écrit :
#9840: Instant preview when leaving math inset becomes freezingly slow after a while ---------------------+------------------------ Reporter: gadmm | Owner: lasgouttes Type: defect | Status: new Priority: normal | Milestone: 2.2.0 Component: general | Version: 2.1.Xdev Severity: normal | Keywords: ---------------------+------------------------ I noticed that, after some time of the same LyX session running, leaving a math inset when instant preview is on becomes painfully slow, to the point where LyX freezes and is "greyed-out" by the OS (indicating non- responsiveness). But, preview generation is supposed to be asynchronous.Here are two (identical) backtraces that I had the time to take while waiting for LyX to become responsive again. {{{ #0 0x00007f91135ead3e in __libc_fork () at ../sysdeps/nptl/fork.c:124 #1 0x0000000000d15225 in lyx::support::ForkedCall::generateChild ( this=0x7ffcfc5b21f0) at ForkedCalls.cpp:459 #2 0x0000000000d119df in lyx::support::ForkedProcess::run ( this=this@entry=0x7ffcfc5b21f0, type=type@entry=lyx::support::ForkedProcess::DontWait) at ForkedCalls.cpp:132 #3 0x0000000000d11ae9 in lyx::support::ForkedCall::startScript(std::string const&, std::shared_ptr<boost::signal<void (int, int), boost::last_value<void>, int, std::less<int>, boost::function<void (int, int)> > >) ...
From http://www.lyx.org/trac/ticket/9840 Scott asked if somebody was going to solve this for 2.2.0. I replied that this was serious enough to have this triaged on the basis of an informed decision. This bug happens because LyX uses fork() as a means to exec() a child process, and fork() can be slow under certain circumstances on Linux (here it gets slower and slower if we leave LyX open for too long). Using fork() seems overkill to me and there seems (to me) to be alternatives (notably QProcess which is cross-platform and would let us get rid of lots of platform-specific code). There also seem to be quick workarounds described in links I gave in the ticket. Given that LyX does not remember the split views on opening (hello #7054), I tend to leave LyX open and hibernate instead of shutting down, so this happens to me systematically. I did my part of the research and I do not know LyX enough to confidently alter cross-platform-critical code. Anybody has an idea? Guillaume
