Eric B Munson wrote: > On Wed, 20 Jul 2011, Andrew Hastings wrote: > >> Eric, >> >> On 07/11/11 10:51, Eric B Munson wrote: >>> Transparent huge pages (THP) make using huge pages on x86(_64) incredibly >>> easy. >>> However, the standard glibc malloc is not setup to optimixe allocations to >>> be >>> fulfilled as THP, relying on khugepaged to scan and merge huge pages when >>> possible. This patch set extends the morecore idea that was originally >>> used to >>> back the heap with hugetlbfs huge pages to ensure that the heap is grown in >>> huge page sized increments. This allows the kernel allocator to start the >>> new >>> area as a huge page rather than wait for promotion. >>> >>> Eric B Munson (3): >>> Add support for THP in morecore >>> Add support to hugeadm for configuring transparent huge pages >>> Add controls to hugectl for new THP related env variables >>> >>> HOWTO | 7 +++- >>> hugeadm.c | 105 >>> +++++++++++++++++++++++++++++++++++++++++++++++ >>> hugectl.c | 17 +++++++- >>> hugeutils.c | 4 ++ >>> libhugetlbfs_internal.h | 1 + >>> man/hugeadm.8 | 35 ++++++++++++++++ >>> man/hugectl.8 | 11 +++++ >>> morecore.c | 84 +++++++++++++++++++++++++++++++++++-- >>> 8 files changed, 258 insertions(+), 6 deletions(-) >> Please consider adding some test cases. >> >> -Andrew Hastings >> Cray Inc. > > I agree that test cases are a good thing for new functionality, but I don't > see > what could be tested. THP availablility is completely up to the kernel, this > method doesn't guarantee that the heap will be on huge pages, it only aligns > allocations so that if there are THP available, they will be used without > having to wait for khugepaged to merge them. So I suppose we could test that > every call to brk is 2MB aligned, but I don't see how that could ever fail. > > Eric
I agree, it's hard to make the tests self-verifying. But I'd find it valuable to have tests that at least exercise the code paths in the library, to help catch any breakages (eg segfaults) from future code changes. And each test could report PASS if it finds hugepages on the heap, INCONCLUSIVE if it doesn't; partial information seems better than none. -Andrew Hastings Cray Inc. ------------------------------------------------------------------------------ Doing More with Less: The Next Generation Virtual Desktop What are the key obstacles that have prevented many mid-market businesses from deploying virtual desktops? How do next-generation virtual desktops provide companies an easier-to-deploy, easier-to-manage and more affordable virtual desktop model.http://www.accelacomm.com/jaw/sfnl/114/51426474/ _______________________________________________ Libhugetlbfs-devel mailing list Libhugetlbfs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libhugetlbfs-devel
