On Fri, Feb 08, 2008 at 03:32:19PM -0800, Christoph Lameter wrote: > On Fri, 8 Feb 2008, Andrew Morton wrote: > > > What about ib_umem_get()? > > Ok. It pins using an elevated refcount. Same as XPmem right now. With that > we effectively pin a page (page migration will fail) but we will > continually be reclaiming the page and may repeatedly try to move it. We > have issues with XPmem causing too many pages to be pinned and thus the > OOM getting into weird behavior modes (OOM or stop lru scanning due to > all_reclaimable set). > > An elevated refcount will also not be noticed by any of the schemes under > consideration to improve LRU scanning performance.
Christoph, I am not sure what you are saying here. With v4 and later, I thought we were able to use the rmap invalidation to remove the ref count that XPMEM was holding and therefore be able to swapout. Did I miss something? I agree the existing XPMEM does pin. I hope we are not saying the XPMEM based upon these patches will not be able to swap/migrate. Thanks, Robin ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
