On Mon, 28 Feb 2011 06:48:18 +0100 Andrea Arcangeli <aarcange@xxxxxxxxxx> wrote: > On Mon, Feb 28, 2011 at 11:17:46AM +0900, KAMEZAWA Hiroyuki wrote: > > BTW, I forget why we always take zone->lru_lock with IRQ disabled.... > > To decrease lock contention in SMP to deliver overall better > performance (not sure how much it helps though). It was supposed to be > hold for a very short time (PAGEVEC_SIZE) to avoid giving irq latency > problems. > memory hotplug uses MIGRATE_ISOLATED migrate types for scanning pfn range without lru_lock. I wonder whether we can make use of it (the function which memory hotplug may need rework for the compaction but migrate_type can be used, I think). Hmm. -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx 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>