On Tue, Nov 15, 2011 at 03:08:31AM +0100, Andrea Arcangeli wrote: > On Tue, Nov 15, 2011 at 03:00:09AM +0100, Andrea Arcangeli wrote: > > I didn't fill that gap but I was reading the code again and I don't > > see why we keep retrying for -EAGAIN in the !sync case. Maybe the > > below is good (untested). I doubt it's good to spend cpu to retry the > > trylock or to retry the migrate on a pinned page by O_DIRECT. In fact > > as far as THP success rate is concerned maybe we should "goto out" > > instead of "goto fail" but I didn't change to that as compaction even > > if it fails a subpage may still be successful at creating order > > 1/2/3/4...8 pages. I only avoid 9 loops to retry a trylock or a page > > under O_DIRECT. Maybe that will save a bit of CPU, I doubt it can > > decrease the success rate in any significant way. I'll test it at the > > next build... > > At the same time also noticed another minor cleanup (also untested, > will text at next build together with some other stuff). > > === > From: Andrea Arcangeli <aarcange@xxxxxxxxxx> > Subject: [PATCH] compaction: move ISOLATE_CLEAN setting out of > compaction_migratepages loop > > cc->sync and mode cannot change within the loop so move it out. > > Signed-off-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> Acked-by: Mel Gorman <mgorman@xxxxxxx> -- Mel Gorman SUSE Labs -- 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>