From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from alln-iport-4.cisco.com (alln-iport-4.cisco.com [173.37.142.91]) by dpdk.org (Postfix) with ESMTP id 2052C2BC5 for ; Fri, 24 Nov 2017 12:24:43 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=7420; q=dns/txt; s=iport; t=1511522683; x=1512732283; h=from:to:cc:subject:date:message-id:references: in-reply-to:mime-version; bh=LNvJFTYUa6Ud1JOMtJZwnPt2cQt6JZ6MuP8KvtHvG/g=; b=Y3qAFfb84Ji/xx66hE0dvvddlh7PNW0zDpYPJICcSnMNcVWmfKtMENi2 fbkaP9cY9jf6jMq/Ucry+tFYRUpbCBwU2vT9eFmQS5iDcykNwVDvYhW0S kXY9zvDPGG5M6WqfMROcg2U090T1VAVrSwvH8iLrQ4RtqwIuXCYmqx+7o 8=; X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: =?us-ascii?q?A0DiAACAABha/5hdJa1cGQEBAQEBAQEBA?= =?us-ascii?q?QEBAQcBAQEBAYJKcmZuJweOF48VgX2RI4VJghEKhTsChFw/GAEBAQEBAQEBAWs?= =?us-ascii?q?dC4UfAQEBAQMtTBACAQgRAwEBASgHMhQJCAEBBA4FCIk2ZKojin0BAQEBAQEBA?= =?us-ascii?q?QEBAQEBAQEBAQEBAQEdgzqCB4FVgWmDK4U8FoVCBYs6jWyJIAKVAZNXlg0CERk?= =?us-ascii?q?BgTkBHzmBUG8VgmIJgn6BTneJWgGBEwEBAQ?= X-IronPort-AV: E=Sophos;i="5.44,447,1505779200"; d="scan'208,217";a="35821248" Received: from rcdn-core-1.cisco.com ([173.37.93.152]) by alln-iport-4.cisco.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 Nov 2017 11:24:42 +0000 Received: from XCH-RTP-017.cisco.com (xch-rtp-017.cisco.com [64.101.220.157]) by rcdn-core-1.cisco.com (8.14.5/8.14.5) with ESMTP id vAOBOfms006856 (version=TLSv1/SSLv3 cipher=AES256-SHA bits=256 verify=FAIL); Fri, 24 Nov 2017 11:24:41 GMT Received: from xch-rtp-017.cisco.com (64.101.220.157) by XCH-RTP-017.cisco.com (64.101.220.157) with Microsoft SMTP Server (TLS) id 15.0.1320.4; Fri, 24 Nov 2017 06:24:41 -0500 Received: from xch-rtp-017.cisco.com ([64.101.220.157]) by XCH-RTP-017.cisco.com ([64.101.220.157]) with mapi id 15.00.1320.000; Fri, 24 Nov 2017 06:24:40 -0500 From: "Hanoch Haim (hhaim)" To: "dev@dpdk.org" CC: "Wu, Jingjing (jingjing.wu@intel.com)" Thread-Topic: [dpdk-dev] net/i40e: latency issue due fix interrupt throttling setting in PF Thread-Index: AdNiEt0UIw83Y/69THKQx+TvljuhYgDA+ARg Date: Fri, 24 Nov 2017 11:24:40 +0000 Message-ID: References: <3f57eb6982af4bb9aae69bce67233d89@XCH-RTP-017.cisco.com> In-Reply-To: <3f57eb6982af4bb9aae69bce67233d89@XCH-RTP-017.cisco.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [64.103.125.33] MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: Re: [dpdk-dev] net/i40e: latency issue due fix interrupt throttling setting in PF 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: Fri, 24 Nov 2017 11:24:43 -0000 Re-sending Hanoh From: Hanoch Haim (hhaim) Sent: Monday, November 20, 2017 5:19 PM To: dev@dpdk.org Cc: Wu, Jingjing (jingjing.wu@intel.com); Hanoch Haim (hhaim) Subject: [dpdk-dev] net/i40e: latency issue due fix interrupt throttling se= tting in PF Hi All, While integrating dpdk17.11 into TRex latest code a new latency issue is ob= served (i40e is very sensitive because it has very good resolution due to = Qos configuration). git bitsec found the following commit. With this commit we observe high spikes of Rx latency (~40usec) vs (~8usec)= . Any idea why? I can send how to reproduce this, it is very simple. cfd662d22e7bddb4ba41dbd1384f8497f38c2b4e is the first bad commit commit cfd662d22e7bddb4ba41dbd1384f8497f38c2b4e Author: Jingjing Wu > Date: Thu Aug 24 09:57:51 2017 +0800 net/i40e: fix interrupt throttling setting in PF As no matter the PF host driver is DPDK or other kernel drivers, they are sharing the same virtchnnl interfaces to communicate to VFs. To follow the generic interface, DPDK PF need to set Interrupt Throttling (ITR) index according to the rxitr_idx from virtchnnl instead of ITR_NONE. Fixes: 6d59e4ea74a6 ("net/i40e: change version number to support Linux = VF") Cc: stable@dpdk.org Signed-off-by: Jingjing Wu > Thanks, Hanoh