From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from alln-iport-2.cisco.com (alln-iport-2.cisco.com [173.37.142.89]) by dpdk.org (Postfix) with ESMTP id 699C47CC2 for ; Mon, 20 Nov 2017 16:18:52 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=5974; q=dns/txt; s=iport; t=1511191132; x=1512400732; h=from:to:cc:subject:date:message-id:mime-version; bh=Wo7lHfueorfEzQwFirjf7++mhB++/q49qNdTCrofXYA=; b=Qd4zHJnZybLD8sycl0SpXPGESLoi6jXqxK/fsXOHD3zBhjkRMNOsynOM CORT4cA3y9czFXSNItkGV3LZra1zof+DroJyOj3g6xSPW8pllfragP9B8 g56RsrOIRRXWgsE4GLRecG9ze1aWXZujgt+xUZiNj6Z4gK/vGL7ZmzrBo M=; X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: =?us-ascii?q?A0DfAABn8RJa/49dJa1bGQEBAQEBAQEBA?= =?us-ascii?q?QEBAQcBAQEBAYJKcmZuJweOF48okxaFSYIRCoU7hQE/GAEBAQEBAQEBAWsdC4V?= =?us-ascii?q?STBIBHCs5FBIBBA4FCIk5ZKsZinUBAQEBAQEBAQEBAQEBAQEBAQEBAR6DNIIHg?= =?us-ascii?q?VWBaYhmhVgFmSKJHAKVAZNVlgUCERkBgTkBHzmBdHoVgy2EX3eKOAGBEwEBAQ?= X-IronPort-AV: E=Sophos;i="5.44,427,1505779200"; d="scan'208,217";a="33961626" Received: from rcdn-core-7.cisco.com ([173.37.93.143]) by alln-iport-2.cisco.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Nov 2017 15:18:51 +0000 Received: from XCH-RTP-019.cisco.com (xch-rtp-019.cisco.com [64.101.220.159]) by rcdn-core-7.cisco.com (8.14.5/8.14.5) with ESMTP id vAKFIoTP021253 (version=TLSv1/SSLv3 cipher=AES256-SHA bits=256 verify=FAIL); Mon, 20 Nov 2017 15:18:51 GMT Received: from xch-rtp-017.cisco.com (64.101.220.157) by XCH-RTP-019.cisco.com (64.101.220.159) with Microsoft SMTP Server (TLS) id 15.0.1320.4; Mon, 20 Nov 2017 10:18:50 -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; Mon, 20 Nov 2017 10:18:50 -0500 From: "Hanoch Haim (hhaim)" To: "dev@dpdk.org" CC: "Wu, Jingjing (jingjing.wu@intel.com)" , "Hanoch Haim (hhaim)" Thread-Topic: [dpdk-dev] net/i40e: latency issue due fix interrupt throttling setting in PF Thread-Index: AdNiEt0UIw83Y/69THKQx+TvljuhYg== Date: Mon, 20 Nov 2017 15:18:50 +0000 Message-ID: <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: [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: Mon, 20 Nov 2017 15:18:53 -0000 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