From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by dpdk.org (Postfix) with ESMTP id C1C49DE3 for ; Tue, 17 Jan 2017 18:49:15 +0100 (CET) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga104.jf.intel.com with ESMTP; 17 Jan 2017 09:49:14 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,245,1477983600"; d="scan'208";a="31746537" Received: from fyigit-mobl1.ger.corp.intel.com (HELO [10.237.220.38]) ([10.237.220.38]) by orsmga002.jf.intel.com with ESMTP; 17 Jan 2017 09:49:13 -0800 To: Shirley Avishour References: Cc: dev@dpdk.org From: Ferruh Yigit Message-ID: <60be9923-501f-0611-698b-40730defbdf3@intel.com> Date: Tue, 17 Jan 2017 17:49:13 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] drops while transmitting to the kni using rte_kni_tx_burst() X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Jan 2017 17:49:16 -0000 On 1/17/2017 12:34 PM, Shirley Avishour wrote: > Hi, > can the KNI_KTHREAD_RESCHEDULE_INTERVAL decrease to lower values than 5 > usecs?? is it effective at all? You are right, it may not be since metric is usecs, and usecs_to_jiffies() most probably will give same value for 5 and lower. Removing that sleep completely (CONFIG_RTE_KNI_PREEMPT_DEFAULT=n) helps a little. > and what is the purpose of KNI_RX_LOOP_NUM? I am not sure I understand > what it does and what should I do with it to improve the performance. Increasing the loop number, also increases the work/sleep ratio, and increasing the performance a little. > > thanks! > > On Mon, Jan 16, 2017 at 5:43 PM, Shirley Avishour > > wrote: > > Hi, > KNI_KTHREAD_RESCHEDULE_INTERVAL is currently set to 5usec. how > should I tweak this value to get better performance? > and can you explain the use of KNI_RX_LOOP_NUM and what can I > possibly modify it to ? > > Thanks! > > > On Mon, Jan 16, 2017 at 4:55 PM, Ferruh Yigit > > wrote: > > On 1/16/2017 2:47 PM, Shirley Avishour wrote: > > Hi, > > As I wrote the kernel thread runs on a dedicated lcore. > > running top while my application is running I see kni_single and the cpu > > usage is really low... > > Is there any rate limitation for transmitting to the kernel interface > > (since packets are being copied in the kernel). > > Yes, kind of, kernel thread sleeps periodically, with a value > defined by > KNI_KTHREAD_RESCHEDULE_INTERVAL. You can try tweaking this > value, if you > want thread do more work, less sleep J > > Also KNI_RX_LOOP_NUM can be updated for same purpose. > > > > > > > On Mon, Jan 16, 2017 at 4:42 PM, Ferruh Yigit > > >> wrote: > > > > On 1/16/2017 12:20 PM, Shirley Avishour wrote: > > > Hi, > > > I have an application over dpdk which is consisted of > the following threads > > > each running on a separate core: > > > 1) rx thread which listens on in a poll mode for traffic > > > 2) 2 packet processing threads (for load balancing) > > > 3) kni thread (which also runs on a separate core). > > > > This is kernel thread, right? Is it bind to any specific core? > > Is it possible that this thread shares the core with 2nd > processing > > thread when enabled? > > > > > > > > the rx thread receives packets and clones them and > transmit a copy > > to the > > > kni and the other packet is sent to the packet > processing unit > > (hashing > > > over 2 threads). > > > the receive traffic rate is 100Mbps. > > > When working with single packet processing thread I am > able to get > > all the > > > 100Mbps towards the kni with no drops. > > > but when I activate my application with 2 packet processing > > threads I start > > > facing drops towards the kni. > > > the way I see it the only difference now is that I have > another > > threads > > > which handles an mbuf and frees it once processing is > completed. > > > Can anyone assist with this case please? > > > > > > Thanks! > > > > > > > > > >