[Bf-committers] Bledner 2.5 - futex problem

[Jacob Heller]

Has anyone else experienced problems associated with the futex system in
2.5?  When using blender, it will lock-up at seemingly random moments.
I haven't found any particular pattern as to what makes it freeze and it
usually happens after 2-10 minutes of using it, but I've gone 45 minutes
at some points before it happens.  Absolutely nothing responds when it
freezes, not even the "close" button at the top of the window.
  
Interestingly, Ubuntu will not even give me the "This window looks like
it's frozen, press here to force quit" dialogue.  I have to go the
system monitor and kill the task.  Looking at the System Monitor when it
happens, under "Waiting channel" it always says "futex_wait" which leads
me to believe it has to do with blender's mutex/futex system.  I'm no
expert at this, but it seems like the multithreading system is mutually
locking any of blender's processes from proceeding.  Blender will not
consume any CPU resources when it freezes.

I have confirmed this on two different systems.  Below are the specs:

Pentium Quad Core Q6600, 2.4 GHz
4 Gb RAM
Nvidia 9800 GT
Ubuntu Linux, 64 Bit

Centrino Dual Core, 2.0 Ghz
2 Gb RAM
Nvidia 7900 Go
Ubuntu Linux, 32 Bit

-Jake