On Thu, Aug 04, 2005 at 03:19:52PM -0700, Christoph Lameter wrote: > There are three possibilites: > > 1. do what cpusets is doing by versioning. > > 2. Have the task notifier access the task_struct information. > See http://lwn.net/Articles/145232/ "A new path to the refrigerator" > > 3. Maybe the easiest: Require mmap_sem to be taken for all policy > accesses. Currently its only require for vma policies. Then we need > to make a copy of the policy at some point so that alloc_pages can > access policy information lock free. This may also allow us to fix > the bind issue if we would f.e. keep a bitmap in the taskstruct or (ab)use > the cpusets map.
None of them seem very attractive to me. I would prefer to just not support external accesses keeping things lean and fast. > > If they cannot afford enough disk space it might be possible > > to do the page migration in swap cache like Hugh proposed. > > This code already exist in the memory hotplug code base and Ray already > had a working implementation for page migration. The migration code will > also be necessary in order to relocate pages with ECC single bit failures > that Russ is working on (of course that will only work for some pages) and > for Mel Gorman's defragmentation approach (if we ever get the split into > differnet types of memory chunks in). Individual physical page migration is quite different from address space migration. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/