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 0A9C2A034D for ; Tue, 11 Jan 2022 05:40:09 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 866C641168; Tue, 11 Jan 2022 05:40:09 +0100 (CET) Received: from gateway23.websitewelcome.com (gateway23.websitewelcome.com [192.185.50.164]) by mails.dpdk.org (Postfix) with ESMTP id C635740041 for ; Tue, 11 Jan 2022 05:40:07 +0100 (CET) Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway23.websitewelcome.com (Postfix) with ESMTP id B5B49103B1 for ; Mon, 10 Jan 2022 22:40:06 -0600 (CST) Received: from md-in-78.webhostbox.net ([116.206.105.125]) by cmsmtp with SMTP id 78x1nGBoIb6UB78x3ng0vU; Mon, 10 Jan 2022 22:40:06 -0600 X-Authority-Reason: nr=8 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=satyaki.co.in; s=default; h=Content-Transfer-Encoding:Content-Type: Message-ID:References:In-Reply-To:Subject:Cc:To:From:Date:MIME-Version:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=4hltunoui9RN4ctRFuwE84gD/EUtYuRgQgXlEeIb8JA=; b=OduSn1svfP3siYqag650/lMHjW +dRjD/gjGMauaU+OkoPHIvXC0ieM+OiQJguszGIMnLGiXjGKaI+X0LfqJAqocuBsShS8R+U35p4Fe skvI5AXwpMwJMD/bCYZxsXrlp1V54liV2rMoxfQSzrylCFztvixKyuWq6NrJl4nWwQsyupegmNcZs W8qVqURWL7OxzsgYG6oKTA0qVmi9B99uwj+sjfRZFWaOOPuqmLvn9AMG0BMeFw0jfsgTyUpbwweam pNVo8/4WDofvb60azrHZ3yltgCqlT2uCSo5WdhhBQZXiKrpHG3/9fqM79kaA/pxJ+s4KNU0dNIiD9 hTOdWTXQ==; Received: from md-in-78.webhostbox.net ([116.206.105.125]:23056) by md-in-78.webhostbox.net with esmtpa (Exim 4.94.2) (envelope-from ) id 1n78x1-003viM-As; Tue, 11 Jan 2022 04:40:03 +0000 MIME-Version: 1.0 Date: Tue, 11 Jan 2022 04:40:02 +0000 From: neeraj.sj@satyaki.co.in To: "Anantharam, Arjun" Cc: users@dpdk.org Subject: Re: [ICE DPDK 21.11] Latency bump at certain rate In-Reply-To: References: User-Agent: Roundcube Webmail/1.4.12 Message-ID: <625bb48cfbe2cd48b7afc79a41f24120@satyaki.co.in> X-Sender: neeraj.sj@satyaki.co.in Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - md-in-78.webhostbox.net X-AntiAbuse: Original Domain - dpdk.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - satyaki.co.in X-BWhitelist: no X-Source-IP: 116.206.105.125 X-Source-L: Yes X-Exim-ID: 1n78x1-003viM-As X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: md-in-78.webhostbox.net [116.206.105.125]:23056 X-Source-Auth: neeraj.sj@satyaki.co.in X-Email-Count: 1 X-Source-Cap: c2F0eWFkcHA7aG9zdGdhdG9yO21kLWluLTc4LndlYmhvc3Rib3gubmV0 X-Local-Domain: yes 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 2022-01-07 21:48, Anantharam, Arjun wrote: > Hi, > > I believe the suggestion here would be to try the new > "rx_low_latency=1" option enabled with DPDK 21.11: > > ยท Low Rx latency (default 0) > > vRAN workloads require low latency DPDK interface for the front haul > interface connection to Radio. By specifying 1 for parameter > rx_low_latency, each completed Rx descriptor can be written > immediately to host memory and the Rx interrupt latency can be reduced > to 2us: > > -a 0000:88:00.0,rx_low_latency=1 > > As a trade-off, this configuration may cause the packet processing > performance degradation due to the PCI bandwidth limitation. > > If they are using an old DPDK version, they can try to backport below > patch > > http://patchwork.dpdk.org/project/dpdk/patch/20210924093429.12068-1-alvinx.zhang@intel.com/ > > > Thanks Hi, We are concerned about dropping the traffic, by limiting its rate to 22 to 24 gbps, rather than allowing complete 40gbps, a formula for cir, pir, ebs and cbs would be more appreciated. Thanks.