From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f47.google.com (mail-wg0-f47.google.com [74.125.82.47]) by dpdk.org (Postfix) with ESMTP id 865F75A9E for ; Thu, 22 Jan 2015 19:27:18 +0100 (CET) Received: by mail-wg0-f47.google.com with SMTP id n12so3354562wgh.6 for ; Thu, 22 Jan 2015 10:27:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=ueV1EmFZRR4vWlt2CqH0D6F4M11O0RGY7ioJYky5uU4=; b=rOliJGUdwVDaCsuZM3m1EhkdVCYtyGyO8Twa8T0b2IvqdxgKRNwAgXxYkt6Fmol2kK lTalk/XxJxZozVwFMYKp5xvgy4Y5kz5JWe2pVyaDVIyS8gTsqQjJmJeKDqKcym4Gb/hD xBqn0Rn1oAXhS54QozmSFsyHq0nq4hgp1ymme8n8MB7Ub9sexn+iQBQPY/XKO87h8Sg/ ovT0/TgW1q31VBfSvMnRWwsNn+MqnnO+4VoioasUH+W5m9Viu5G07c2hSC+fVA0sqmxI ZKGzvqybt9MmdKRwmCl5w+0pmivjYZdqoUE0eM5V0jhqNlsfd1//b7WNrJ43iI3tkrNA vqWA== MIME-Version: 1.0 X-Received: by 10.194.23.6 with SMTP id i6mr5738726wjf.26.1421951232531; Thu, 22 Jan 2015 10:27:12 -0800 (PST) Sender: lukego@gmail.com Received: by 10.27.75.203 with HTTP; Thu, 22 Jan 2015 10:27:12 -0800 (PST) In-Reply-To: References: <20150119130221.GB21790@hmsreliant.think-freely.org> <20150120151118.GD18449@hmsreliant.think-freely.org> <20150120161453.GA5316@bricha3-MOBL3> <54BF9D59.7070104@bisdn.de> <20150121130234.GB10756@bricha3-MOBL3> <54BFA7D5.7020106@bisdn.de> <20150121132620.GC10756@bricha3-MOBL3> <20150121114947.0753ae87@urahara> <20150121205404.GB32617@hmsreliant.think-freely.org> <53D2253B-DE20-486E-ADF0-DA02AAB1EF35@netgate.com> Date: Thu, 22 Jan 2015 19:27:12 +0100 X-Google-Sender-Auth: YrkZ3DUTsyYKbQ5i8Zd3eArr6N4 Message-ID: From: Luke Gorrie To: Jay Rolette Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.15 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: Thu, 22 Jan 2015 18:27:18 -0000 On 22 January 2015 at 14:29, Jay Rolette wrote: > Microseconds matter. Scaling up to 100GbE, nanoseconds matter. > True. Is there a cut-off point though? Does one nanosecond matter? AVX512 will fit a 64-byte packet in one register and move that to or from memory with one instruction. L1/L2 cache bandwidth per server is growing on a double-exponential curve (both bandwidth per core and cores per CPU). I wonder if moving data around in cache will soon be too cheap for us to justify worrying about. I suppose that 1500 byte wide registers are still a ways off though ;-) Cheers! -Luke (begging your indulgence for wandering off on a tangent)