From owner-freebsd-net@FreeBSD.ORG Wed Sep 21 08:55:00 2005 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 21CAF16A41F for ; Wed, 21 Sep 2005 08:55:00 +0000 (GMT) (envelope-from david.mao@thomson.net) Received: from dmzraw4.extranet.tce.com (dmzraw4.extranet.tce.com [157.254.234.139]) by mx1.FreeBSD.org (Postfix) with ESMTP id 618C743D46 for ; Wed, 21 Sep 2005 08:54:59 +0000 (GMT) (envelope-from david.mao@thomson.net) Received: from indyvss2.am.thmulti.com (unknown [157.254.92.61]) by dmzraw4.extranet.tce.com (Postfix) with ESMTP id 354391744 for ; Wed, 21 Sep 2005 08:54:58 +0000 (GMT) Received: from localhost (localhost [127.0.0.1]) by indyvss2.am.thmulti.com (Postfix) with ESMTP id 2538344624 for ; Wed, 21 Sep 2005 08:54:58 +0000 (GMT) Received: from indyvss2.am.thmulti.com ([127.0.0.1]) by localhost (indyvss2 [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 10986-01-93 for ; Wed, 21 Sep 2005 08:54:55 +0000 (GMT) Received: from indysmailcs01.am.thmulti.com (indysmailcs01.am.thmulti.com [157.254.96.5]) by indyvss2.am.thmulti.com (Postfix) with ESMTP id ECA8744602 for ; Wed, 21 Sep 2005 08:54:54 +0000 (GMT) Received: from indysmailbh01.am.thmulti.com ([157.254.96.4]) by indysmailcs01.am.thmulti.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 21 Sep 2005 03:54:55 -0500 Received: from tahkexch2k.ap.thmulti.com ([141.11.13.12]) by indysmailbh01.am.thmulti.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 21 Sep 2005 03:54:54 -0500 Received: from bjngsmail01.ap.thmulti.com ([10.11.70.35]) by tahkexch2k.ap.thmulti.com with Microsoft SMTPSVC(5.0.2195.6713); Wed, 21 Sep 2005 16:54:14 +0800 X-MimeOLE: Produced By Microsoft Exchange V6.0.6603.0 content-class: urn:content-classes:message MIME-Version: 1.0 Date: Wed, 21 Sep 2005 16:54:13 +0800 Message-ID: <31021C278A7A6B4AB95E9A085C3552181CE58F@bjngsmail01> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: About guideline of parameters tuning while in polling mode. Thread-Index: AcW+igfR4Zek9+GpT2STJrbV2STo7g== From: "Mao Shou Yan" To: X-OriginalArrivalTime: 21 Sep 2005 08:54:14.0105 (UTC) FILETIME=[0A830490:01C5BE8A] X-Virus-Scanned: amavisd-new at thomson.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: About guideline of parameters tuning while in polling mode. X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Sep 2005 08:55:00 -0000 Hi, everybody Can anyone give some guidelines on tuning the following parameters when the system is in polling mode and works in high throughput network environment. Thanks a lot! =20 =20 /* * EM_TIDV - Transmit Interrupt Delay Value=20 * Valid Range: 0-65535 (0=3Doff) * Default Value: 64 * This value delays the generation of transmit interrupts in units of * 1.024 microseconds. Transmit interrupt reduction can improve CPU * efficiency if properly tuned for specific network traffic. If the * system is reporting dropped transmits, this value may be set too high * causing the driver to run out of available transmit descriptors. */ #define EM_TIDV 64 =20 /* * EM_TADV - Transmit Absolute Interrupt Delay Value (Not valid for 82542/82543/82544) * Valid Range: 0-65535 (0=3Doff) * Default Value: 64 * This value, in units of 1.024 microseconds, limits the delay in which a * transmit interrupt is generated. Useful only if EM_TIDV is non-zero, * this value ensures that an interrupt is generated after the initial * packet is sent on the wire within the set amount of time. Proper tuning, * along with EM_TIDV, may improve traffic throughput in specific * network conditions. */ #define EM_TADV 64 =20 /* * EM_RDTR - Receive Interrupt Delay Timer (Packet Timer)=20 * Valid Range: 0-65535 (0=3Doff) * Default Value: 0 * This value delays the generation of receive interrupts in units of 1.024 * microseconds. Receive interrupt reduction can improve CPU efficiency if * properly tuned for specific network traffic. Increasing this value adds * extra latency to frame reception and can end up decreasing the throughput * of TCP traffic. If the system is reporting dropped receives, this value * may be set too high, causing the driver to run out of available receive * descriptors. * * CAUTION: When setting EM_RDTR to a value other than 0, adapters * may hang (stop transmitting) under certain network conditions. * If this occurs a WATCHDOG message is logged in the system event log. * In addition, the controller is automatically reset, restoring the * network connection. To eliminate the potential for the hang * ensure that EM_RDTR is set to 0. */ #define EM_RDTR 0 =20 /* * Receive Interrupt Absolute Delay Timer (Not valid for 82542/82543/82544) * Valid Range: 0-65535 (0=3Doff) * Default Value: 64 * This value, in units of 1.024 microseconds, limits the delay in which a * receive interrupt is generated. Useful only if EM_RDTR is non-zero, * this value ensures that an interrupt is generated after the initial * packet is received within the set amount of time. Proper tuning, * along with EM_RDTR, may improve traffic throughput in specific network * conditions. */ #define EM_RADV 64 =20