From patchwork Sun Jan 8 03:55:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cheng Li X-Patchwork-Id: 1722928 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=openvswitch.org (client-ip=140.211.166.136; helo=smtp3.osuosl.org; envelope-from=ovs-dev-bounces@openvswitch.org; receiver=) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4NqNY45T4hz23fc for ; Sun, 8 Jan 2023 14:56:23 +1100 (AEDT) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id A26C360BC4; Sun, 8 Jan 2023 03:56:20 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org A26C360BC4 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9hvCDWtnkQR3; Sun, 8 Jan 2023 03:56:20 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp3.osuosl.org (Postfix) with ESMTPS id EE53B60A9D; Sun, 8 Jan 2023 03:56:18 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org EE53B60A9D Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id CA758C0032; Sun, 8 Jan 2023 03:56:18 +0000 (UTC) X-Original-To: dev@openvswitch.org Delivered-To: ovs-dev@lists.linuxfoundation.org Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 224A3C002D for ; Sun, 8 Jan 2023 03:56:17 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id F129681F24 for ; Sun, 8 Jan 2023 03:56:16 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org F129681F24 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7WYIvBlTVm2p for ; Sun, 8 Jan 2023 03:56:15 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 92F6A81F20 Received: from chinatelecom.cn (prt-mail.chinatelecom.cn [42.123.76.219]) by smtp1.osuosl.org (Postfix) with ESMTP id 92F6A81F20 for ; Sun, 8 Jan 2023 03:56:14 +0000 (UTC) HMM_SOURCE_IP: 172.18.0.218:58346.138189483 HMM_ATTACHE_NUM: 0000 HMM_SOURCE_TYPE: SMTP Received: from clientip-218.88.38.83 (unknown [172.18.0.218]) by chinatelecom.cn (HERMES) with SMTP id 179CB2800B8; Sun, 8 Jan 2023 11:56:05 +0800 (CST) X-189-SAVE-TO-SEND: +lic121@chinatelecom.cn Received: from ([218.88.38.83]) by app0025 with ESMTP id e8e32236c0fc4975b12e74f4ac502119 for dev@openvswitch.org; Sun, 08 Jan 2023 11:56:11 CST X-Transaction-ID: e8e32236c0fc4975b12e74f4ac502119 X-Real-From: lic121@chinatelecom.cn X-Receive-IP: 218.88.38.83 X-MEDUSA-Status: 0 From: Cheng Li To: dev@openvswitch.org, ktraynor@redhat.com Date: Sun, 8 Jan 2023 03:55:45 +0000 Message-Id: <1673150145-29368-1-git-send-email-lic121@chinatelecom.cn> X-Mailer: git-send-email 1.8.3.1 Subject: [ovs-dev] [PATCH] docs: Add HyperThreading notes for auto-lb usage. X-BeenThere: ovs-dev@openvswitch.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: ovs-dev-bounces@openvswitch.org Sender: "dev" In my test, if one logical core is pinned to PMD thread while the other logical(of the same physical core) is not. The PMD performance is affected the by the not-pinned logical core load. This maks it difficult to estimate the loads during a dry-run. Signed-off-by: Cheng Li Reviewed-by: Simon Horman Acked-by: Kevin Traynor --- Documentation/topics/dpdk/pmd.rst | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Documentation/topics/dpdk/pmd.rst b/Documentation/topics/dpdk/pmd.rst index 9006fd4..b220199 100644 --- a/Documentation/topics/dpdk/pmd.rst +++ b/Documentation/topics/dpdk/pmd.rst @@ -312,6 +312,10 @@ If not set, the default variance improvement threshold is 25%. when all PMD threads are running on cores from a single NUMA node. In this case cross-NUMA datapaths will not change after reassignment. + For the same reason, please ensure that the pmd threads are pinned to SMT + siblings if HyperThreading is enabled. Otherwise, PMDs within a NUMA may + not have the same performance. + The minimum time between 2 consecutive PMD auto load balancing iterations can also be configured by::