On Wed, Apr 29, 2009 at 01:33:02PM -0700, Ralph Campbell wrote: > Correct. This is what I was referring to when I said > hardware support would be needed to make use of the 2.6.27 > page mapping callback notifications. I don't know of any > current HCAs which support this sort of dynamic mapping.
You can use the callback notifications to pin the memory and register it with the HCA when a new VMA is allocated, and do the reverse when a VMA is removed. Paging at the HCA level is only necessary to avoid pinning the ram. MPI may be a special enough case where this is actually doable without a huge overcommit. It would be very interesting to see /proc/PID/smaps information for a running MPI job to compute how many unallocated pages are present in a job. -- Jason Gunthorpe <[email protected]> (780)4406067x832 Chief Technology Officer, Obsidian Research Corp Edmonton, Canada _______________________________________________ general mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
