On Mon, Feb 14, 2005 at 10:50:42AM -0800, Dave Hansen wrote: > On Mon, 2005-02-14 at 07:52 -0600, Robin Holt wrote: > > The node mask is a list of allowed. This is intended to be as near > > to a one-to-one migration path as possible. > > If that's the case, it would make the kernel internals a bit simpler to > only take a "from" and "to" node, instead of those maps. You'll end up > making multiple syscalls, but that shouldn't be a problem.
Then how do you handle overlapping nodes. If I am doing a 5->4, 4->3, 3->2, 2->1 shift in the memory placement and had only a from and to node, I would end up calling multiple times. This would end up in memory shifting from 5->4 on the first, 4->3 on the second, ... with the end result of all memory shifting to a single node. With the array-of-node maps, you make a single pass across the address space. This results in a clean mapping without the userspace needing to know which nodes the pages are on. On a seperate topic, I would guess the syscall time is trivial compared to the time to walk the page tables. Thanks, Robin - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
