From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 8A82B5A1F for ; Wed, 21 Jan 2015 04:45:07 +0100 (CET) Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga103.jf.intel.com with ESMTP; 20 Jan 2015 19:41:07 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.09,439,1418112000"; d="scan'208";a="654066537" Received: from pgsmsx102.gar.corp.intel.com ([10.221.44.80]) by fmsmga001.fm.intel.com with ESMTP; 20 Jan 2015 19:45:04 -0800 Received: from shsmsx102.ccr.corp.intel.com (10.239.4.154) by PGSMSX102.gar.corp.intel.com (10.221.44.80) with Microsoft SMTP Server (TLS) id 14.3.195.1; Wed, 21 Jan 2015 11:44:26 +0800 Received: from shsmsx101.ccr.corp.intel.com ([169.254.1.64]) by shsmsx102.ccr.corp.intel.com ([169.254.2.238]) with mapi id 14.03.0195.001; Wed, 21 Jan 2015 11:44:24 +0800 From: "Wang, Zhihong" To: "Richardson, Bruce" , Neil Horman Thread-Topic: [dpdk-dev] [PATCH 0/4] DPDK memcpy optimization Thread-Index: AQHQM+g93pBJjc9asEOmHYpPzg55ApzITFZAgADkUQ+AALooEA== Date: Wed, 21 Jan 2015 03:44:23 +0000 Message-ID: References: <1421632414-10027-1-git-send-email-zhihong.wang@intel.com> <20150119130221.GB21790@hmsreliant.think-freely.org> <20150120151118.GD18449@hmsreliant.think-freely.org> <20150120161453.GA5316@bricha3-MOBL3> In-Reply-To: <20150120161453.GA5316@bricha3-MOBL3> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] [PATCH 0/4] DPDK memcpy optimization X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Jan 2015 03:45:08 -0000 > -----Original Message----- > From: Richardson, Bruce > Sent: Wednesday, January 21, 2015 12:15 AM > To: Neil Horman > Cc: Wang, Zhihong; dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH 0/4] DPDK memcpy optimization >=20 > On Tue, Jan 20, 2015 at 10:11:18AM -0500, Neil Horman wrote: > > On Tue, Jan 20, 2015 at 03:01:44AM +0000, Wang, Zhihong wrote: > > > > > > > > > > -----Original Message----- > > > > From: Neil Horman [mailto:nhorman@tuxdriver.com] > > > > Sent: Monday, January 19, 2015 9:02 PM > > > > To: Wang, Zhihong > > > > Cc: dev@dpdk.org > > > > Subject: Re: [dpdk-dev] [PATCH 0/4] DPDK memcpy optimization > > > > > > > > On Mon, Jan 19, 2015 at 09:53:30AM +0800, zhihong.wang@intel.com > wrote: > > > > > This patch set optimizes memcpy for DPDK for both SSE and AVX > platforms. > > > > > It also extends memcpy test coverage with unaligned cases and > > > > > more test > > > > points. > > > > > > > > > > Optimization techniques are summarized below: > > > > > > > > > > 1. Utilize full cache bandwidth > > > > > > > > > > 2. Enforce aligned stores > > > > > > > > > > 3. Apply load address alignment based on architecture features > > > > > > > > > > 4. Make load/store address available as early as possible > > > > > > > > > > 5. General optimization techniques like inlining, branch > > > > > reducing, prefetch pattern access > > > > > > > > > > Zhihong Wang (4): > > > > > Disabled VTA for memcpy test in app/test/Makefile > > > > > Removed unnecessary test cases in test_memcpy.c > > > > > Extended test coverage in test_memcpy_perf.c > > > > > Optimized memcpy in arch/x86/rte_memcpy.h for both SSE and AVX > > > > > platforms > > > > > > > > > > app/test/Makefile | 6 + > > > > > app/test/test_memcpy.c | 52 +- > > > > > app/test/test_memcpy_perf.c | 238 +++++--= - > > > > > .../common/include/arch/x86/rte_memcpy.h | 664 > > > > +++++++++++++++------ > > > > > 4 files changed, 656 insertions(+), 304 deletions(-) > > > > > > > > > > -- > > > > > 1.9.3 > > > > > > > > > > > > > > Are you able to compile this with gcc 4.9.2? The compilation of > > > > test_memcpy_perf is taking forever for me. It appears hung. > > > > Neil > > > > > > > > > Neil, > > > > > > Thanks for reporting this! > > > It should compile but will take quite some time if the CPU doesn't su= pport > AVX2, the reason is that: > > > 1. The SSE & AVX memcpy implementation is more complicated than > AVX2 > > > version thus the compiler takes more time to compile and optimize 2. > > > The new test_memcpy_perf.c contains 126 constants memcpy calls for > > > better test case coverage, that's quite a lot > > > > > > I've just tested this patch on an Ivy Bridge machine with GCC 4.9.2: > > > 1. The whole compile process takes 9'41" with the original > > > test_memcpy_perf.c (63 + 63 =3D 126 constant memcpy calls) 2. It take= s > > > only 2'41" after I reduce the constant memcpy call number to 12 + 12 > > > =3D 24 > > > > > > I'll reduce memcpy call in the next version of patch. > > > > > ok, thank you. I'm all for optimzation, but I think a compile that > > takes almost > > 10 minutes for a single file is going to generate some raised eyebrows > > when end users start tinkering with it > > > > Neil > > > > > Zhihong (John) > > > > Even two minutes is a very long time to compile, IMHO. The whole of DPDK > doesn't take that long to compile right now, and that's with a couple of = huge > header files with routing tables in it. Any chance you could cut compile = time > down to a few seconds while still having reasonable tests? > Also, when there is AVX2 present on the system, what is the compile time > like for that code? >=20 > /Bruce Neil, Bruce, Some data first. Sandy Bridge without AVX2: 1. original w/ 10 constant memcpy: 2'25"=20 2. patch w/ 12 constant memcpy: 2'41"=20 3. patch w/ 63 constant memcpy: 9'41"=20 Haswell with AVX2: 1. original w/ 10 constant memcpy: 1'57"=20 2. patch w/ 12 constant memcpy: 1'56"=20 3. patch w/ 63 constant memcpy: 3'16"=20 Also, to address Bruce's question, we have to reduce test case to cut down = compile time. Because we use: 1. intrinsics instead of assembly for better flexibility and can utilize mo= re compiler optimization=20 2. complex function body for better performance=20 3. inlining=20 This increases compile time. But I think it'd be okay to do that as long as we can select a fair set of = test points. It'd be great if you could give some suggestion, say, 12 points. Zhihong (John)