ed to allocate memory. This was undesirable, as users invoking memory page migration exected to happen when the placement changed, not some unspecified time later when the task needed more memory. It is now trivial to handle the page migration at the same time as the per-vma rebinding is done. The routine cpuset.c:update_nodemask(), which handles changing a cpusets memory placement ('mems') now checks for the special case of being asked to write a placement that is the same as before. It was harmless enough before to just recompute everything again, even though nothing had changed. But page migration is a heavy weight operation - moving pages about. So now it is worth avoiding that if asked to move a cpuset to its current location. Signed-off-by: Paul Jackson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds ơn