On Wed, Oct 24, 2012 at 01:25:52PM -0700, Andrew Morton wrote: > On Wed, 24 Oct 2012 22:45:52 +0300 > "Kirill A. Shutemov" wrote: > > > On Wed, Oct 24, 2012 at 12:22:53PM -0700, Andrew Morton wrote: > > > > > > I'm thinking that such a workload would be the above dd in parallel > > > with a small app which touches the huge page and then exits, then gets > > > executed again. That "small app" sounds realistic to me. Obviously > > > one could exercise the zero page's refcount at higher frequency with a > > > tight map/touch/unmap loop, but that sounds less realistic. It's worth > > > trying that exercise as well though. > > > > > > Or do something else. But we should try to probe this code's > > > worst-case behaviour, get an understanding of its effects and then > > > decide whether any such workload is realisic enough to worry about. > > > > Okay, I'll try few memory pressure scenarios. > > Thanks. > > > Meanwhile, could you take patches 01-09? Patch 09 implements simpler > > allocation scheme. It would be nice to get all other code tested. > > Or do you see any other blocker? > > I think I would take them all, to get them tested while we're still > poking at the code. It's a matter of getting my lazy ass onto reviewing > the patches. > > The patches have a disturbing lack of reviewed-by's, acked-by's and > tested-by's on them. Have any other of the MM lazy asses actually > spent some time with them yet? Andrea Revieved-by previous version of the patchset, but I've dropped the tag after rebase to v3.7-rc1 due not-so-trivial conflicts. Patches 2, 3, 4, 7, 10 had conflicts. Mostly due new MMU notifiers interface. I mentioned that in cover letter. -- Kirill A. Shutemov