On ia64 we had a virtual frame_table to allow for better handling of sparse memory configs. Has x86 considered anything similar? I see that init_frametable() is currently allocating 32bytes per page for everything up to max_page. This can consume a pretty significant chunk of memory if nodes are discontiguous. Anyone motivated to fix it? Thanks, Alex _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On 26/08/2009 22:20, "Alex Williamson" <alex.williamson@hp.com> wrote:> On ia64 we had a virtual frame_table to allow for better handling of > sparse memory configs. Has x86 considered anything similar? I see that > init_frametable() is currently allocating 32bytes per page for > everything up to max_page. This can consume a pretty significant chunk > of memory if nodes are discontiguous. Anyone motivated to fix it?Easily fixed if there''s a reason to. Not really many x86 systems have discontiguous memory. K. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Thu, 2009-08-27 at 07:30 +0100, Keir Fraser wrote:> On 26/08/2009 22:20, "Alex Williamson" <alex.williamson@hp.com> wrote: > > > On ia64 we had a virtual frame_table to allow for better handling of > > sparse memory configs. Has x86 considered anything similar? I see that > > init_frametable() is currently allocating 32bytes per page for > > everything up to max_page. This can consume a pretty significant chunk > > of memory if nodes are discontiguous. Anyone motivated to fix it? > > Easily fixed if there''s a reason to. Not really many x86 systems have > discontiguous memory.Right, but commodity systems are definitely getting bigger quickly, and it''s only a matter of time. I''ll toss in my vote that the frame_table should be optimized sooner rather than later. I might even be able to test it on a system that''s wasting more memory than we''d like there. Thanks, Alex _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel