From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx165.postini.com [74.125.245.165]) by kanga.kvack.org (Postfix) with SMTP id D5B096B0007 for ; Thu, 21 Feb 2013 11:47:53 -0500 (EST) Received: from /spool/local by e28smtp09.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 21 Feb 2013 22:15:57 +0530 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id D8629E0057 for ; Thu, 21 Feb 2013 22:18:47 +0530 (IST) Received: from d28av02.in.ibm.com (d28av02.in.ibm.com [9.184.220.64]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r1LGlf2J19529842 for ; Thu, 21 Feb 2013 22:17:42 +0530 Received: from d28av02.in.ibm.com (loopback [127.0.0.1]) by d28av02.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r1LGleXU009772 for ; Fri, 22 Feb 2013 03:47:43 +1100 From: "Aneesh Kumar K.V" Subject: [RFC PATCH -V2 00/21] THP support for PPC64 Date: Thu, 21 Feb 2013 22:17:07 +0530 Message-Id: <1361465248-10867-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: benh@kernel.crashing.org, paulus@samba.org Cc: linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org 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. I still have considerable number of FIXME!! in the patchset mostly related to PPC64 mm susbsytem. Those would require closer review and once we are clear on those changes, I will drop those FIXME!! with necessary comments. 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 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@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org