On 04/01/2014 12:21 PM, Linus Torvalds wrote: > On Tue, Apr 1, 2014 at 9:11 AM, Rik van Riel <riel@xxxxxxxxxx> wrote: >> >> Memory pressure is not necessarily caused by the same process >> whose accessed bit we just cleared. Memory pressure may not >> even be caused by any process's virtual memory at all, but it >> could be caused by the page cache. > > If we have that much memory pressure on the page cache without having > any memory pressure on the actual VM space, then the swap-out activity > will never be an issue anyway. > > IOW, I think all these scenarios are made-up. I'd much rather go for > simpler implementation, and make things more complex only in the > presence of numbers. Of which we have none. We've been bitten by the lack of a properly tracked accessed bit before, but admittedly that was with the KVM code and EPT. I'll add my Acked-by: to Shaohua's original patch then, and will keep my eyes open for any problems that may or may not materialize... Shaohua? -- All rights reversed -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>