Hi, This patchset adds transparent huge page support for PPC64. I am marking the series to linux-mm because the PPC64 implementation required few interface changes to core THP code. TODO: * ppc64 KVM related changes * batch support for hpte invalidate * powernv still doesn't boot * hash preload support in update_mmu_cache_pmd Some numbers: The latency measurements code from Anton found at http://ozlabs.org/~anton/junkcode/latency2001.c THP disabled 64K page size ------------------------ [root@llmp24l02 ~]# ./latency2001 8G 8589934592 731.73 cycles 205.77 ns [root@llmp24l02 ~]# ./latency2001 8G 8589934592 743.39 cycles 209.05 ns [root@llmp24l02 ~]# THP disabled large page via hugetlbfs ------------------------------------- [root@llmp24l02 ~]# ./latency2001 -l 8G 8589934592 416.09 cycles 117.01 ns [root@llmp24l02 ~]# ./latency2001 -l 8G 8589934592 415.74 cycles 116.91 ns THP enabled 64K page size. ---------------- [root@llmp24l02 ~]# ./latency2001 8G 8589934592 405.07 cycles 113.91 ns [root@llmp24l02 ~]# ./latency2001 8G 8589934592 411.82 cycles 115.81 ns [root@llmp24l02 ~]# We are close to hugetlbfs in latency and we can achieve this with zero config/page reservation. Most of the allocations above are fault allocated. I haven't really measured the collapse alloc impact. Another test that does 50000000 random access over 1GB area goes from 2.65 seconds to 1.07 seconds with this patchset. Changes from RFC V2: * Address review comments * More code cleanup and patch split Changes from RFC V1: * HugeTLB fs now works * Compile issues fixed * rebased to v3.8 * Patch series reorded so that ppc64 cleanups and MM THP changes are moved early in the series. This should help in picking those patches early. Thanks, -aneesh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>