From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f54.google.com (mail-pb0-f54.google.com [209.85.160.54]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 044662C008D for ; Thu, 21 Mar 2013 19:17:32 +1100 (EST) Received: by mail-pb0-f54.google.com with SMTP id rr4so2037245pbb.41 for ; Thu, 21 Mar 2013 01:17:31 -0700 (PDT) Message-ID: <514AC211.2030500@gmail.com> Date: Thu, 21 Mar 2013 16:17:21 +0800 From: Simon Jeons MIME-Version: 1.0 To: "Aneesh Kumar K.V" Subject: Re: [RFC PATCH -V2 00/21] THP support for PPC64 References: <1361465248-10867-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> In-Reply-To: <1361465248-10867-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: paulus@samba.org, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Aneesh, On 02/22/2013 12:47 AM, Aneesh Kumar K.V wrote: > 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 Can this benchmark use for x86? > > 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