From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 420C1A0C43 for ; Fri, 26 Nov 2021 18:22:42 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 2E50C42750; Fri, 26 Nov 2021 18:22:42 +0100 (CET) Received: from mail-pf1-f179.google.com (mail-pf1-f179.google.com [209.85.210.179]) by mails.dpdk.org (Postfix) with ESMTP id C35FA4274C for ; Fri, 26 Nov 2021 18:22:40 +0100 (CET) Received: by mail-pf1-f179.google.com with SMTP id 8so9540226pfo.4 for ; Fri, 26 Nov 2021 09:22:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=H4/yQ94cv8LpnSO0GVpS6yRJzE5TrRCPgVxH63i/YMY=; b=iA6wG8xKGTHoUGZ8G4EPtukOP7RUb4ulpUV9c/fD9anQiIo9l0aUGx/ZpbPSyRAyFw tSqmLL3IIYgaqv3OFlP4tQOlOsTpWNSbDtHoRegN2drEtAudsKOccX/s5HvDSTi/XO+j pRIH2BwhCRQiDrckkaINT9ntDQML299b6OuVDTSrWGhZCJFdMfoH1J5UcZqTubfvGB03 ip3cVea9H0S7JTOCbPihTqrpzTtJWC6UsTQcUz9vfju2T/mRRsqSSZGmFIz4A31HzKYt hE3F5inOd5iv3De9i1f4WUDN0rllp3D1Yi6Gx26jY42VjP6dEv2palIhyGLKVJUkfkao biaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=H4/yQ94cv8LpnSO0GVpS6yRJzE5TrRCPgVxH63i/YMY=; b=GoNNcWxh/E+YNS8NVIsipA+Vqgzps/Wy34aRzM2bRDqIw0VE2QXtRC5rwXP6LXzp/m hbYeyRhrR4RejvWnvO1pKRXxhETQKdoY9fNkdy9v7hzyVFbzg4HO4iewA2LcwCzbTL09 X3CqtSdyitYvkgnBZQ2ogT+jnza+WJmx7VKvBQm7LYpjLherSIoxSnoAiTj71fiM65xI 7P3oz0F+agn4G2IUICCEsMKWLQhUxtsvTLzPXMGpWxn1YuaVTGNRrVT116LcaTMuxETE yd68j5Zluimes80t61x7rGVXIAcWLaJ4MuUvUy8+I1/Xcg+p17akQ62zVi3KlPMXld2x raRw== X-Gm-Message-State: AOAM531g6GQA0ire4tJISfnsEP/DPatLEEKS1cImug5rk810Ew+UT/Oq Xv0FvIJumJbdS4FOVrh4o7/0iA== X-Google-Smtp-Source: ABdhPJxEfakfAh7vRGKe/VcD1FCFTAnI2RxeHcEpyCAfWlwKm8babkvIZMLZ2gXE5bigz74vkNEReg== X-Received: by 2002:a63:e06:: with SMTP id d6mr22712364pgl.449.1637947359975; Fri, 26 Nov 2021 09:22:39 -0800 (PST) Received: from hermes.local (204-195-33-123.wavecable.com. [204.195.33.123]) by smtp.gmail.com with ESMTPSA id ep15sm12115253pjb.3.2021.11.26.09.22.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Nov 2021 09:22:39 -0800 (PST) Date: Fri, 26 Nov 2021 09:22:36 -0800 From: Stephen Hemminger To: Staffan Wiklund Cc: users Subject: Re: Impact on DPDK application when using the multi-process feature? Message-ID: <20211126092236.7a16dab0@hermes.local> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: users-bounces@dpdk.org On Fri, 26 Nov 2021 13:27:40 +0100 Staffan Wiklund wrote: > Hello > > I wonder if you please can help me with some questions regarding the DPDK > multi-process feature? > > If a primary process and the secondary processes all execute on different > CPU cores, > what limitations are there on the secondary processes when using DPDK > functions > for initialization of EAL and for handling ethernet devices? > > That is, is a secondary process allowed to call the rte_eal_init function > or any of > the rte_eth_xxx functions? Secondary process has to call rte_eal_init() with secondary (or auto flag). Which of the rte_eth_xxx functions are you asking about? > What will happen if a secondary process calls any of these DPDK functions? > > The reason for these questions is that I would like to execute 3-4 DPDK > applications that > now executes as stand-alone applications as one primary process and the > other > applications as secondary processes. All these processes will share memory > which > shall be used to improve the speed of communication between the > applications. Several applications do this. > The applications currently use DPDK for Ethernet based communication and I > would > like to learn what needs to be modified in order to be able to execute them > as a > primary and secondary processes using DPDK shared memory. > > Best regards > Staffan To be honest, my experience is that not all functions work on all drivers with the multi-process model. The documentation mostly covers the ones that don't but you have to be careful and test with particular drivers and use cases.