Hi Dan, On Thu, Mar 22, 2012 at 03:27:35PM +0100, Andrea Arcangeli wrote: > current code would optimally perform, if all nodes are busy and there > aren't idle cores (or only idle siblings). I guess I'll leave the HT > optimizations for later. I probably shall measure this again with HT off. I added the latest virt measurement with KVM for kernel build and memhog. I also measured how much I'd save by increasing the knuma_scand pass frequency (scan_sleep_pass_millisecs) from 10sec default (5000 value) to 30sec. I also tried 1min but it was within error range of 30sec. 10sec -> 30sec is also almost within error range showing the cost is really tiny. Luckily the numbers were totally stable by running a -j16 loop on both VM (each VM had 12 vcpus on a host with 24 CPUs) and the error was less than 1sec for each kernel build (on tmpfs obviously and totally stripped down userland in both guest and host). http://www.kernel.org/pub/linux/kernel/people/andrea/autonuma/autonuma_bench-20120322.pdf slide 11 and 12. This is with THP on, with THP off things would be different likely but hey THP off is like 20% slower or more on a kernel build in guest in the first place. I'm satisfied with the benchmarks results so far and more will come soon, but now it's time to go back coding and add THP native migration. That will benefit everyone, from cpuset in userland to numa/sched. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>