From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <yuliang.li@yale.edu> Received: from mail-lf0-f44.google.com (mail-lf0-f44.google.com [209.85.215.44]) by dpdk.org (Postfix) with ESMTP id 3E7A62A5E for <users@dpdk.org>; Wed, 28 Feb 2018 06:01:24 +0100 (CET) Received: by mail-lf0-f44.google.com with SMTP id v9so1574375lfa.11 for <users@dpdk.org>; Tue, 27 Feb 2018 21:01:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yale.edu; s=googleprd; h=mime-version:from:date:message-id:subject:to; bh=nVcVV8+Y+KY0Qo73bE3AR7ZvMLnPJ10bODaBBR0sE/c=; b=2L3tAK+Mdpv/hNXUM2xE/MxViA7WPmxfRx70sknb4VEcYaqQmgQraS5hMr012C/9Bg W4R8MkEkf/iTiThj00XKjugrlmFpluyMzkp3LszDMuTdGduzfvHvuLdMNIHHL2jpK9wO Yn2wl1DFs8quR2BM6EnhXQZ5Q3aTD8wTR/ftU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=nVcVV8+Y+KY0Qo73bE3AR7ZvMLnPJ10bODaBBR0sE/c=; b=jMVHtS0nDnxnHIDomlaJSSm6qhOKMVkuUEiFWtf7no1BwEdpySJLy9Lx4i5zhWTXiu yGlSLo1sPJ5L8L67RDn1eV/yyz8VL64gZwuxb0o35eUu+qM9vOdzBoGs+oBvLb0IAxyS YLbB7+2btPcl8OjFQKczsCXV3xcUFjp1pXVMTwfvtF9nOiQx6a8ZFTXXod01VA9mneRS hLi5oTZ3ovEMFpi0ETvCF8FJozipgba6LUtE8rGbyN90tYqDetVwLL6dW1LreUMgTRsg mvvtL2O20Xn7RocyO7HtIEcY0zb3nsY5/wmNN6AOg5uxb5kh4cZGm9tI/9MPYMcsFUO4 nuEA== X-Gm-Message-State: APf1xPDH/lRUyH2qC49+YK3GVht4vnQpxF4iV4SsJr2b0EMxV8HTLfSH nY0R2d+O5xwNVIyBcCBIL0gHTD/+rAGxTjW63r9Xp4Js X-Google-Smtp-Source: AG47ELu+wBtuBTHC+MkObJj3Nr5LG2rGnmhanFtggadxVhnpUwQJ/UMCUDtSPBzz3VC/iqnjibhIRsnH2JC8sW/vEsA= X-Received: by 10.25.215.68 with SMTP id o65mr12325760lfg.90.1519794083390; Tue, 27 Feb 2018 21:01:23 -0800 (PST) MIME-Version: 1.0 Received: by 10.25.27.17 with HTTP; Tue, 27 Feb 2018 21:01:22 -0800 (PST) From: Yuliang Li <yuliang.li@yale.edu> Date: Wed, 28 Feb 2018 00:01:22 -0500 Message-ID: <CAECc8johtEVEe5L8bwB1ZFFTPzPDQ22jKqYVLjVUfVDwFKV0ng@mail.gmail.com> To: users@dpdk.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: [dpdk-users] occasionally ~300us delay X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK usage discussions <users.dpdk.org> List-Unsubscribe: <https://dpdk.org/ml/options/users>, <mailto:users-request@dpdk.org?subject=unsubscribe> List-Archive: <http://dpdk.org/ml/archives/users/> List-Post: <mailto:users@dpdk.org> List-Help: <mailto:users-request@dpdk.org?subject=help> List-Subscribe: <https://dpdk.org/ml/listinfo/users>, <mailto:users-request@dpdk.org?subject=subscribe> X-List-Received-Date: Wed, 28 Feb 2018 05:01:24 -0000 Hi all, I am using dpdk to generate packets. Specifically, I have a list of <packet Pi, time Ti>, meaning I want to send Pi at Ti. I wait for Ti by while (rte_get_tsc_cycles()<Ti). However, sometimes I see a delay of around 300us of sending packets, i.e., the sending time of some Pi is around Ti+300us. It looks like the program just pauses by 300us, and then resumes. Does anyone know why? Thanks, -- Yuliang Li PhD student Department of Computer Science Yale University