From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] app/testpmd: adds mlockall() to fix pages Date: Tue, 12 Sep 2017 22:14:01 +0200 Message-ID: <1863612.973jloI4LL@xps> References: <22990026376b08418cb0eb6f028840c03e89f47f.1505221429.git.echaudro@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, jingjing.wu@intel.com, john.mcnamara@intel.com To: Aaron Conole , Eelco Chaudron Return-path: Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by dpdk.org (Postfix) with ESMTP id 2319EFFA for ; Tue, 12 Sep 2017 22:14:05 +0200 (CEST) In-Reply-To: List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 12/09/2017 16:50, Aaron Conole: > Eelco Chaudron writes: > > > 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. > > > > Signed-off-by: Eelco Chaudron > > Acked-by: Aaron Conole It is interesting, but why make it in testpmd? Maybe it should be documented in this guide: http://dpdk.org/doc/guides/linux_gsg/nic_perf_intel_platform.html