Samuel, Thanks a lot ! This is exactly the kind of clarification I've been looking for and it's great to know it's been added to the official docs. hwloc is a pleasure to work with.
On Thu, May 31, 2012 at 11:28 AM, Samuel Thibault <samuel.thiba...@inria.fr>wrote: > Hello, > > Vlad, le Thu 31 May 2012 16:49:00 +0200, a écrit : > > This might be a naive question, but I'd like to clarify nonetheless: to > provide > > any sort of affinity guarantees, hwloc mem binding APIs assume that any > memory > > allocation is done exclusively via hwloc_alloc_membind() and friends? > And if I > > use "raw" calls to malloc() or posix_memalign() etc then any ensuing > affinity > > will be incidental at best? > > It seems the documentation lacks explanation about that indeed. I have > added the following text: > > Memory binding can be done three ways: > > - explicit memory allocation thanks to hwloc_alloc_membind and friends: > the > binding will have effect on the memory allocated by these functions. > - implicit memory binding through binding policy: hwloc_set_membind and > friends only define the current policy of the process, which will be > applied to the subsequent calls to malloc() and friends. > - migration of existing memory ranges, thanks to hwloc_set_area_membind() > and friends, which move already-allocated data. > > Does it answer your question? (i.e. the first way doesn't have effect on > malloc, while the second way does) > > Samuel > _______________________________________________ > hwloc-users mailing list > hwloc-us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/hwloc-users >
