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 B2C3B426AE for ; Tue, 3 Oct 2023 10:49:29 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 7707C402A9; Tue, 3 Oct 2023 10:49:29 +0200 (CEST) Received: from mail-ej1-f43.google.com (mail-ej1-f43.google.com [209.85.218.43]) by mails.dpdk.org (Postfix) with ESMTP id C838E4026B for ; Tue, 3 Oct 2023 10:49:27 +0200 (CEST) Received: by mail-ej1-f43.google.com with SMTP id a640c23a62f3a-9ad810be221so112185466b.2 for ; Tue, 03 Oct 2023 01:49:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1696322967; x=1696927767; darn=dpdk.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=Vd20pEcijkzpedYkBRNI1cXYPWFdWuTvgF7Su+703kA=; b=YfAaQ8SrQt8J6nipUrcU3kELJS7LbmkjKODYNhLTm1dxkNsTwbngn2Awnyp+zeyer1 vUQqTtUNvkW6BoOjlAMkv1imNVil6QWH7AaWtvGogDSpF9t550V5QhFXoyYbioAi6aj+ SsrDt2UGMaikseknCcEmXA/CBlThr5EVmbvz6f1UKh7dXVmRns3qjeWphoU6wmJammpP KDkW2zLhnSO4wx3UucBtLe2mpt0/LLHRoH+6aMAOodS2Qnc12RZhRcmHQmWfsBSCVEnc sHHllR3bWUGxP/SepAwcO8HXt3r4K4hIirr2oIgLByVJP04Xj6nWagonu0ZOUkJyuYVS lBXQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696322967; x=1696927767; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Vd20pEcijkzpedYkBRNI1cXYPWFdWuTvgF7Su+703kA=; b=hQ/wKWfVmKQdl5WD/miqwzLr4piMpZKHF+DN23cyfF8ue8DZFovZQhs5HFlH22dWR6 Rm8dfmxbZlCJcgHymywHpPNQNoQ1pmpW3N4paByqRKXgNhe/hLVh/NfDKrXmBNwgapXn NXcnfyX8nQRM5kEQQOugdCpopeq6LtaH8YmsXXcrtSXxNgbEZhNCutPecp8dUBdR8OFT eFaeEecK/DdpFfxcEjoCYyasSJprSqn6zyyVCUqvG5rTfvouBrA9p7cCM7r8CokdbYNr YNWRbWdB2tlBftlYZS1sr4pLn94SsUS7ScyBWdqLBz61T64NmXPXCUG53yYuqlsRgyMC cOWQ== X-Gm-Message-State: AOJu0Yy1nwrkWGHEHFQPGhkjbCdVMMSqGDG1yNe2gh9gnocTwTF6ShMS VjlEdICbicjPFHTxjK8ldeSoYqcIVPTwUlKG+90uMPy1wx4= X-Google-Smtp-Source: AGHT+IFf4zFbz9o/qvyMtNmYgGDBaVBmHqvtBryGolI3ZtjY1JB07AExX5oMvUZzSlu16j72gKXA+kGHxhu2NxR82k8= X-Received: by 2002:a17:906:cc5a:b0:9a1:891b:6eed with SMTP id mm26-20020a170906cc5a00b009a1891b6eedmr12660392ejb.76.1696322967196; Tue, 03 Oct 2023 01:49:27 -0700 (PDT) MIME-Version: 1.0 References: <20231002142133.27590624@hermes.local> In-Reply-To: <20231002142133.27590624@hermes.local> From: Antonio Di Bacco Date: Tue, 3 Oct 2023 10:49:16 +0200 Message-ID: Subject: Re: tap device speed To: Stephen Hemminger Cc: users@dpdk.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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 I understand, could we use another solution ? Like a memif interface in DPDK and libmemif in Linux? On Mon, Oct 2, 2023 at 11:21=E2=80=AFPM Stephen Hemminger wrote: > > On Mon, 2 Oct 2023 21:13:03 +0200 > Antonio Di Bacco wrote: > > > I'm doing a test where we have a couple of tap devices, the two > > devices are seen by testpmd that is setup in forward mode. > > > > On the linux side, the two tap devices are confined in different > > network namespaces and in one namespace we have an iperf server while > > on the other namespace the iperf client sending either UDP or TCP. > > > > I expected a bandwidth in the range of few gpbs while the actual > > measured bandwidth is a few gigabits. > > > > I suppose I need to configure the tap devices with optimized > > parameters but I don't know where to look for advice. > > > > If I try to use the loopback interface I can get something 40 gbps > > with a command like this: > > > > iperf -c 127.0.0.1 -u -i 1 -b 40g -t 10 -l 40000 > > > > . > > Sorry TAP device is inherently slow. It requires copies to/from Linux > kernel. You are doing well if you get 1 million packets per second. > > One thing to check is that checksum is not being done twice.