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    SubjectFix NUMA problems in transparent hugepages and KSM
    The current transparent hugepages daemon can mess up local
    memory affinity on NUMA systems. When it copies memory to a
    huge page it does not necessarily keep it on the same
    node as the local allocations.

    While fixing this I also found some more related issues:
    - The NUMA policy interleaving for THP was using the small
    page size, not the large parse size.
    - KSM and THP copies also did not preserve the local node
    - The accounting for local/remote allocations in the daemon
    was misleading.
    - There were no VM statistics counters for THP, which made it
    impossible to analyze.

    At least some of the bug fixes are 2.6.38 candidates IMHO
    because some of the NUMA problems are pretty bad. In some workloads
    this can cause performance problems.

    What can be delayed are GFP_OTHERNODE and the statistics changes.

    Git tree:

    git:// thp-numa

    Andi Kleen (8):
    Fix interleaving for transparent hugepages
    Change alloc_pages_vma to pass down the policy node for local policy
    Preserve local node for KSM copies
    Preserve original node for transparent huge page copies
    Use correct numa policy node for transparent hugepages
    Add __GFP_OTHER_NODE flag
    Use GFP_OTHER_NODE for transparent huge pages
    Add VM counters for transparent hugepages

    include/linux/gfp.h | 13 ++++++++---
    include/linux/vmstat.h | 11 ++++++++-
    mm/huge_memory.c | 49 +++++++++++++++++++++++++++++++++--------------
    mm/ksm.c | 3 +-
    mm/mempolicy.c | 16 +++++++-------
    mm/page_alloc.c | 2 +-
    mm/vmstat.c | 17 ++++++++++++++-
    7 files changed, 78 insertions(+), 33 deletions(-)


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