On Thu, May 28, 2009 at 9:12 AM, Ivan Novick <[email protected]> wrote: > Hi, > I would like to detect cases of false sharing in my program. > By this I mean cases where multiple threads are both trying to write data to > different memory locations but those locations are closest enough in memory > that they are on the on the same cache line. > The result would be delays on threads even though there are enough CPU's to > do the work. > Are there any tools in valgrind to do this?
No, but it wouldn't be too hard to write a new one that did this. For each cache-line-sized chunk of memory, you'd record which thread last wrote to it and when, and then if another thread wrote to a chunk sufficiently soon after a previous thread you'd give a warning. You could record thread numbers and addresses and stack traces and the like, there'd be trade-offs in how much overhead you'd have vs. how much info you'd get in each report. Nick ------------------------------------------------------------------------------ Register Now for Creativity and Technology (CaT), June 3rd, NYC. CaT is a gathering of tech-side developers & brand creativity professionals. Meet the minds behind Google Creative Lab, Visual Complexity, Processing, & iPhoneDevCamp as they present alongside digital heavyweights like Barbarian Group, R/GA, & Big Spaceship. http://p.sf.net/sfu/creativitycat-com _______________________________________________ Valgrind-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/valgrind-users
