From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id 475E37D4E for ; Thu, 14 Sep 2017 09:22:31 +0200 (CEST) Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4F8E3356D6; Thu, 14 Sep 2017 07:22:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 4F8E3356D6 Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=echaudro@redhat.com Received: from rhvm.imac (ovpn-116-76.ams2.redhat.com [10.36.116.76]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5DA6178211; Thu, 14 Sep 2017 07:22:29 +0000 (UTC) To: Thomas Monjalon Cc: dev@dpdk.org, jingjing.wu@intel.com References: <22990026376b08418cb0eb6f028840c03e89f47f.1505221429.git.echaudro@redhat.com> <4147502.SWF1kaKTU5@xps> From: Eelco Chaudron Organization: Red Hat Message-ID: <2ff0680b-b73f-fd1f-9f41-caa38a13bcde@redhat.com> Date: Thu, 14 Sep 2017 09:22:38 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <4147502.SWF1kaKTU5@xps> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 14 Sep 2017 07:22:30 +0000 (UTC) Subject: Re: [dpdk-dev] [PATCH] app/testpmd: adds mlockall() to fix pages X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: echaudro@redhat.com List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 14 Sep 2017 07:22:31 -0000 On 13/09/17 11:39, Thomas Monjalon wrote: > 12/09/2017 15:08, Eelco Chaudron: >> Call the mlockall() function, to attempt to lock all of its process >> memory into physical RAM, and preventing the kernel from paging any >> of its memory to disk. >> >> When using testpmd for performance testing, depending on the code path >> taken, we see a couple of page faults in a row. These faults effect >> the overall drop-rate of testpmd. On Linux the mlockall() call will >> prefault all the pages of testpmd (and the DPDK libraries if linked >> dynamically), even without LD_BIND_NOW. > Does it work on FreeBSD? I do not have a FreeBSD setup, but from the documentation I've read the call is supported by FreeBSD. If some one has a working setup, please give this patch a quick try. > Is there any drawback? > Do we need to add an option for it? The only drawback I can think of is that with this change memory phyiscal memory is consumed as pages are pre-loaded. For testpmd (just loaded not doing anything) this is 2MB vs 35MB of memory used. I do not think this yields an extra option.