From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f176.google.com (mail-ig0-f176.google.com [209.85.213.176]) by dpdk.org (Postfix) with ESMTP id B0CE67F6D for ; Mon, 25 Jan 2016 14:43:23 +0100 (CET) Received: by mail-ig0-f176.google.com with SMTP id t15so35434505igr.0 for ; Mon, 25 Jan 2016 05:43:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=semihalf-com.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=v78M7M/ev+fP4++stO0U8P1YH7KZLObr5981aJNBWv0=; b=hRGhjS322kipoeCQj5NjlHHMfPxDruSqad7f7YHj5x5voOtWDq6q17LypLtzYrvUE2 Dc9uhXxNUJHIf1XrROxVsu+CvlzwOr/32FaTSarTRp780tWXmf4+Od4lqi2FYB4R+5NN pGD+CJiMb76crB3/H/2Cs6DGYJijfb1Tsmy/6MhZxVKaZYcaplCTFOHeo1dzvF0YGne8 10BuarofGm2WnHTa5aQFA+1vBft2wmMSmmoc5LW9qtyDV295Tvx4M5po/xB2f3IQA5Tp s2DuNPLgffmtqLSM9yebruYPx5a9raA5clsP336nyPshAUF/RDIrIx8vFAaIHHnBBPqu inLQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc:content-type; bh=v78M7M/ev+fP4++stO0U8P1YH7KZLObr5981aJNBWv0=; b=C5YtA1p0pu11PRDpuBR5z8jrVMi+sKYRchhFObvf4aX+L8+UDSR4u50hlHXqRsH4Lf o5xGuQOkmxJzx7n98l/28cf9CjBE6dywb6wZTuBNm7U3lvB3hE4eJf0CY++Dk+SjHbdf U5Zq/9/7PNfC8gt+bopeDTAy5day/akZ2bCIfofoa+UPazGl7BdJ2SXNXyVrBseofDce qkU+ZBM4ua/TWs2T4QVEngbV/R4BT0FA1t/RVg1X+y/ZliNjBF2mYMAhpIB/UcHzez7v nb3pwmB9+OQb2tZZJmjX5CIB92bNPi7BxxlpEyZYczgj9Jf+nEee4gMq2VM4oeeVeSOr +2yQ== X-Gm-Message-State: AG10YORaIO5UL2Y5GXrmucJkNnsXZ7F0JzgGYELHsp3sNlAe6BhaAo9YCZ+iz71tMrTD+2E/yl6nsF1PakevOw== X-Received: by 10.50.78.165 with SMTP id c5mr746618igx.29.1453729403199; Mon, 25 Jan 2016 05:43:23 -0800 (PST) MIME-Version: 1.0 Received: by 10.64.227.161 with HTTP; Mon, 25 Jan 2016 05:43:03 -0800 (PST) In-Reply-To: References: From: Andriy Berestovskyy Date: Mon, 25 Jan 2016 14:43:03 +0100 Message-ID: To: Masoud Moshref Javadi Content-Type: text/plain; charset=UTF-8 Cc: "users@dpdk.org" Subject: Re: [dpdk-users] high jitter in dpdk kni X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 Jan 2016 13:43:24 -0000 Hi Masoud, Try a low latency kernel (i.e. linux-image-lowlatency). Andriy On Mon, Jan 25, 2016 at 2:15 PM, Masoud Moshref Javadi wrote: > I see. But this should not be the issue in Ping. > By the way, I checked the timestamps of sending and receiving times at the > kni sample application (kni_ingress and kni_egress methods). The RTT at > that level is OK (0.1ms) and it seems the jitter comes from the kni kernel > module. > > On Mon, Jan 25, 2016 at 12:29 AM Freynet, Marc (Nokia - FR) < > marc.freynet@nokia.com> wrote: > >> Hi, >> >> Some months ago we had a problem with the KNI driver. >> Our DPDK application forwards to the Linux kernel through KNI the SCTP PDU >> received from the Eth NIC. >> In one configuration, the SCTP port Source and Destination were constant >> on all SCTP connections. >> This is a known SCTP issue as in the multi processor environment, the SCTP >> stack uses the port Source and Destination to hash the processor that will >> run the SCTP context in the kernel. >> SCTP cannot use the IP address as a hash key thanks to the SCTP multi >> homing feature. >> >> As all SCTP PDU on all SCTP connections where processed by the same Core, >> this creates a bottle neck and the KNI interface starts creating Jitter and >> even was losing PDU when sending the SCTP PDU to the IP Linux kernel stack. >> >> I am wondering if in a previous release it you not be possible to add KNI >> a kind of load sharing with different queues on different cores to forward >> the received PDU to the IP Linux stack. >> >> "Bowl of rice will raise a benefactor, a bucket of rice will raise a >> enemy.", Chinese proverb. >> >> FREYNET Marc >> Alcatel-Lucent France >> Centre de Villarceaux >> Route de Villejust >> 91620 NOZAY France >> >> Tel: +33 (0)1 6040 1960 >> Intranet: 2103 1960 >> >> marc.freynet@nokia.com >> >> -----Original Message----- >> From: users [mailto:users-bounces@dpdk.org] On Behalf Of EXT Masoud >> Moshref Javadi >> Sent: samedi 23 janvier 2016 15:18 >> To: users@dpdk.org >> Subject: [dpdk-users] high jitter in dpdk kni >> >> I see jitter in KNI RTT. I have two servers. I run kni sample application >> on one, configure its IP and ping an external interface. >> >> sudo -E build/kni -c 0xaaaa -n 4 -- -p 0x1 -P --config="(0,3,5)" >> sudo ifconfig vEth0 192.168.1.2/24 >> ping 192.168.1.3 >> >> This is the ping result: >> 64 bytes from 192.168.1.2: icmp_seq=5 ttl=64 time=1.93 ms >> 64 bytes from 192.168.1.2: icmp_seq=6 ttl=64 time=0.907 ms >> 64 bytes from 192.168.1.2: icmp_seq=7 ttl=64 time=3.15 ms >> 64 bytes from 192.168.1.2: icmp_seq=8 ttl=64 time=1.96 ms >> 64 bytes from 192.168.1.2: icmp_seq=9 ttl=64 time=3.95 ms >> 64 bytes from 192.168.1.2: icmp_seq=10 ttl=64 time=2.90 ms >> 64 bytes from 192.168.1.2: icmp_seq=11 ttl=64 time=0.933 ms >> >> The ping delay between two servers without kni is 0.170ms. >> I'm using dpdk 2.2. >> >> Any thought on how to keep KNI delay predictable? >> >> Thanks >> -- Andriy Berestovskyy