On Sun, Feb 28, 2010 at 12:49:14PM -0500, Rik van Riel wrote: > On 02/26/2010 09:32 AM, Johannes Weiner wrote: > >On Wed, Feb 24, 2010 at 01:39:46PM -0800, Andrew Morton wrote: > >>On Mon, 22 Feb 2010 20:49:07 +0100 Johannes Weiner<hannes@xxxxxxxxxxx> > >>wrote: > >> > >>>This patch makes the VM be more careful about activating mapped file > >>>pages in the first place. The minimum granted lifetime without > >>>another memory access becomes an inactive list cycle instead of the > >>>full memory cycle, which is more natural given the mentioned loads. > >> > >>iirc from a long time ago, the insta-activation of mapped pages was > >>done because people were getting peeved about having their interactive > >>applications (X, browser, etc) getting paged out, and bumping the pages > >>immediately was found to help with this subjective problem. > >> > >>So it was a latency issue more than a throughput issue. I wouldn't be > >>surprised if we get some complaints from people for the same reasons as > >>a result of this patch. > > > >Agreed. Although we now have other things in place to protect them once > >they are active (VM_EXEC protection, lazy active list scanning). > > You think we'll need VM_EXEC protection on the inactive list > after your changes? So far I personally did not experience anything that would indicate the need for it. But I would consider it an option if Andrew's worries turned out to be true. -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>