On Fri, Apr 6, 2012 at 5:21 PM, Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> wrote: > On Friday 06 April 2012 08:40:56 Minchan Kim wrote: >> On Fri, Apr 6, 2012 at 1:32 AM, Bartlomiej Zolnierkiewicz < >> b.zolnierkie@xxxxxxxxxxx> wrote: >> >> > In isolate_freepages() check each page in a pageblock >> > instead of checking only first pages of pageblock_nr_pages >> > intervals (suitable_migration_target(page) is called before >> > isolate_freepages_block() so if page is "unsuitable" whole >> > pageblock_nr_pages pages will be ommited from the check). >> > It greatly improves possibility of finding free pages to >> > isolate during compaction_alloc() phase. >> > >> >> I doubt how this can help keeping free pages. >> Now, compaction works by pageblock_nr_pages unit so although you work by >> per page, all pages in a block would have same block type. >> It means we can't pass suitable_migration_target. No? > > suitable_migration_target() only checks first page of pageblock_nr_pages > block (1024 normal 4KiB pages in my test case cause there is no hugepage > support on ARM) and pages in pageblock_nr_pages block can have different > types otherwise I would not see improvement from this patch. How? pages in a block should be same type. -- Kind regards, Minchan Kim -- 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>