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 1AC77459D8 for ; Thu, 19 Sep 2024 23:53:55 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id CDE6D400EF; Thu, 19 Sep 2024 23:53:54 +0200 (CEST) Received: from mail-pf1-f177.google.com (mail-pf1-f177.google.com [209.85.210.177]) by mails.dpdk.org (Postfix) with ESMTP id 558FB4026A for ; Thu, 19 Sep 2024 23:53:53 +0200 (CEST) Received: by mail-pf1-f177.google.com with SMTP id d2e1a72fcca58-7178df70f28so1054373b3a.2 for ; Thu, 19 Sep 2024 14:53:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20230601.gappssmtp.com; s=20230601; t=1726782832; x=1727387632; 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=iiGzLSo2+3Kq06Di8CxpReS3jOFvEt57/uRA2ks5wtE=; b=0srqyN7ODWXdpu8pd8f6bQcJ+1H32eI9ape02NyM/YlNzR42LYs2yLmJYuEhPZJnEV jNa2Tqe2E9FP0kQ41KWqBQey0O8S1iao3dt1yJCDD7saVJahRrwiV1qwfRGyLav++wTt FvIZMBibptIGmUaNKSWUj+MckBnDVGpiwN3td/HemY0PRxDfY+BeQ/VIIOkOIhvQs27W 3/1KtcZl+VqMC1wW9pmeyweu0Z/Zznsn7GQXEHPu2O9ngLSa0vposRw9SkMx4TzW0tEx oYrNYpXdjuMsO+tr4pUxKF69DaQA3o02xU1jVWgUDEpA5+MrBDvOKUFPkKPFyeybHY+n 0/3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726782832; x=1727387632; 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=iiGzLSo2+3Kq06Di8CxpReS3jOFvEt57/uRA2ks5wtE=; b=nXCUsFBlw8anaEqUWF1Ga7hp+7YSfqhvoz4sPV9bxeMLNfMzuKwc996cEbEGJezJ2M a/NAoK3S+/XRwXmfdjApreJIYoVlG6Db3ARDpQFjpLr1Ec2lGDCN7XYiRds1gof+JGtJ bj1C8gg6dCjVX57h66YTU2GsKe7E1wuJ3xRn85r5MmBk8UZF5L4JVifbW2e08uo5JFRf LfLZeMCJ+7iBZ16a+L4g3sRwftEdCQXA7yiDH/nKfaoeyG2YpPirLsLr5v5gc0W6/dr3 xyLiyVb6jQkwHsuq8jL9GCCDXNnZVVQCKpwTtFqiUFba92cwfZ2kMmDEddtm+I9zMvXW KCGA== X-Gm-Message-State: AOJu0YwXQpMlN+Me0dc54yET67Qssxp3AQ8CYI1z0nsjND+fHpTTWRaD cEomT6gxfByQ/xoRD72YBBNS92QOa6yYZO5UFnTfcWODBkoSd/sdvLuPICzzaVA= X-Google-Smtp-Source: AGHT+IHzDP1XC9u779e1sxcjJd+YcKtNuiA0+YQrlbYScJgstdNvXw5BgU+jjW8gg7bjvxGWnp/Y9w== X-Received: by 2002:a05:6a21:70c8:b0:1ce:d9a2:66ed with SMTP id adf61e73a8af0-1d30aa368dfmr937469637.48.1726782832330; Thu, 19 Sep 2024 14:53:52 -0700 (PDT) Received: from hermes.local (204-195-96-226.wavecable.com. [204.195.96.226]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-71944a9831esm8718950b3a.24.2024.09.19.14.53.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 Sep 2024 14:53:52 -0700 (PDT) Date: Thu, 19 Sep 2024 14:53:50 -0700 From: Stephen Hemminger To: Isaac Boukris Cc: users@dpdk.org Subject: Re: Accuracy of rte_get_tsc_hz() compared to linux Message-ID: <20240919145350.423df1ce@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 Thu, 19 Sep 2024 01:04:40 +0300 Isaac Boukris wrote: > Hi, > > On Intel(R) Xeon(R) Gold 6130 CPU @ 2.10GHz (see lscpu output at the end). > > The rte_get_tsc_hz() returns 2100000 KHz but using it causes our > timestamps to lag behind real time (roughly a sec per 10 min). I > noticed the kernel uses 2095082 KHz and in fact it gives much better > results. FYI there is a bug from 2022 about this: https://bugs.dpdk.org/show_bug.cgi?id=959