On Wed, 10 Feb 2010, Derek Gaston wrote: > So... I got tired of not being able to use threading with > Hermites... so I finally went in there and fixed it.
I'd call this more of a "workaround" than a "fix", but it's still a big improvement over my original status of "bug" or my recent upgrade to "unsupported feature". ;-) > I fixed it by turning off the caching that Roy was doing when > libMesh is compiled with thread support. Note that this might slow > things down if you happen to have compiled your library with thread > support... but aren't actually using threads. > > But I think the trade off is nice... you can now use threads to > solve fourth order problems... no nasty bugs to grab you... or > asserts to hit. I agree. I'm curious, though - could you quantify the slowdown? Recalculating all those conversion coefficients on every basis function on every quadrature point sounds pretty ugly, but I'd be happy to be told that I was just prematurely optimizing. > Also... through this process I spotted a couple of other > non-threadsafe operations going on in some of the constraint > projection stuff (mostly having to do with PointLocator > initialization). I put proper locks around that using the "Double > Checked Lock Pattern" for speed... so it's good to go now. Thanks! I need to pick your brain sometime about locking, BTW. I've got some more subtlely non-thread-safe code (the ALE stuff) that could be made thread-safe in one of a few ways, but choosing which would require me to know more about various lock/mutex costs than I do now. > Roy: Take a look at what I did and let me know if you don't like it. Will do ASAP, but it may take a few days. I just got back from a brief conference & vacation; 72 new emails... --- Roy ------------------------------------------------------------------------------ SOLARIS 10 is the OS for Data Centers - provides features such as DTrace, Predictive Self Healing and Award Winning ZFS. Get Solaris 10 NOW http://p.sf.net/sfu/solaris-dev2dev _______________________________________________ Libmesh-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-devel
