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 A389C45DA8; Mon, 25 Nov 2024 20:44:20 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 675C140BA0; Mon, 25 Nov 2024 20:44:20 +0100 (CET) Received: from mail-pg1-f182.google.com (mail-pg1-f182.google.com [209.85.215.182]) by mails.dpdk.org (Postfix) with ESMTP id 5265040BA0 for ; Mon, 25 Nov 2024 20:44:19 +0100 (CET) Received: by mail-pg1-f182.google.com with SMTP id 41be03b00d2f7-7f8b01bd40dso3405356a12.0 for ; Mon, 25 Nov 2024 11:44:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20230601.gappssmtp.com; s=20230601; t=1732563857; x=1733168657; darn=dpdk.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=TD4cTj+iG312VhnjrHoKlSl3LptbvrPWf+7lRFnuygk=; b=Yk6n2JmfmEGwWDDlqnv6Prypj/s70O3jjldKCxDYgCuyiASwZ9Q/k06RCELW3+0N82 RokpiO5xulTwzjumhN9MSesck3oQCaBrJpQQnowkEVypdV3QEE+UIsne+4VmIBnc3B0N OxDK06hKnGMRZ+qpl4K7bc1J+c9Df50UBmHxtyZaYkIRfMB5A8cf6e7iPee0Bcw/UZew JS+QL1RWrbcVCr5FlS+xdzBcD1Zz6zMqz+R4zI9pj+eVTzFsnRbiNsgvEk36QYQ1oOtI YayW2HC8TLOJL5cqn8dQXNCq0QuLnwx1qWCJfZu/LWOAjDwXrdOu6JRbQpCK+iaoIlMv kNdw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1732563857; x=1733168657; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=TD4cTj+iG312VhnjrHoKlSl3LptbvrPWf+7lRFnuygk=; b=m7hFuYecAYI/HAwY7Su1b2+TteKT47qNul3Z1MetctDNdioJ3cvLnItHpReSyCd4WY Z6VOfc50cWwRYrvHheJIa4KWmDix7j44goMZX18LnTdSswXD8aB2X8Zt+d59IZJtAUIg Eh/WHN438ow3bsxGYSCZR1LdAlCkcMQmbcRyj16Tq76o5nVSJ/E8NtDcOVDfqTKuIGWS m3TYY70R5A+DvGOQYBjCLma6qyo2ViE0DfdMaKps2nZBTgc/VNX9/3msMCmNci5U3pCt aGwsHMKvBr+QXTJpZCX9cuQoMJbSW9qtx3Fj2b/xAACpSl++Pm8KvJhYsE+jX4hav4Z0 rohg== X-Gm-Message-State: AOJu0YwTV1p9mSJZmG+KcKmjiF9EHeOzXHQQu6lu7ixHIEBQZDnEo1BA o55uFR0fOjqt+9ZzClYAfQ7qDQA3aU4cK5+QoSkyze/wJ9HGqFX18JWJvmTFRUk= X-Gm-Gg: ASbGncuEVd8XXESXD4DL0FakpPvprDgD1MDdgFeiSpc18goX8x8O+wm5eECz1yPZzPY /1+gS7xUlGPfShzZNlwBipe8ZxZjH0O4qizk/nrZYoOsLC6/0O0kACDYmkXDFa1yCHedQvCGi93 eZfZwNzq64pbQa1ucpFnYFpx0RbwGFj5iY/TCfUxvd9EE6eeNLNU+vXtsKATZ9SGndiga92gAAF mOdBXoRwlM308QJpa9f87yCESXYAhGSJySvyq5ZJkVq5aJhW9j8tQB5Om02peaTYJPlu17O5zYH o2uuTBiurfl56NHxxzI5sT1mw0Y= X-Google-Smtp-Source: AGHT+IFb3ivleQVW5cQAycgyy1sUvz8hDf8yx1sh2aINeivXkSZvqnSiPL6H3JfX/TFUrPH7a1Aghw== X-Received: by 2002:a17:902:db0e:b0:20c:68af:a4e3 with SMTP id d9443c01a7336-214e6f09464mr10354195ad.22.1732563857348; Mon, 25 Nov 2024 11:44:17 -0800 (PST) Received: from hermes.local (204-195-96-226.wavecable.com. [204.195.96.226]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2129dc2ab8csm68526025ad.277.2024.11.25.11.44.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Nov 2024 11:44:17 -0800 (PST) Date: Mon, 25 Nov 2024 11:44:10 -0800 From: Stephen Hemminger To: Jie Hai Cc: , , , Morten =?UTF-8?B?QnLDuHJ1cA==?= , Chengwen Feng , Huisong Li , Subject: Re: [PATCH] examples/l3fwd: fix Tx performance deteriorate Message-ID: <20241125114410.2e8fe285@hermes.local> In-Reply-To: <20241122071336.18470-1-haijie1@huawei.com> References: <20241122071336.18470-1-haijie1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On Fri, 22 Nov 2024 15:13:36 +0800 Jie Hai wrote: > The application send packets only when the buffer is full, or the > buffer is empty and the number of packets to be sent extends half > of the buffer. > > The change of MAX_PKT_BURST increases TX buffer size, while the > default size of local cache on each lcore is 256, which not greater > than the limit of transmitting. That would make the mbuf not on the > local cache be frequently used and the performance deteriorates. > > This problem can be solved by making the TX threshold smaller than > the local cache size. For example, use the '--mbcache' parameter to > make the local cache greater. This patch optimizes the default > performance by lowering TX threshold. > > Fixes: d5c4897ecfb2 ("examples/l3fwd: add option to set Rx burst size") > > Signed-off-by: Jie Hai Do the other variants of l3fwd have the same problem?