From owner-freebsd-current@FreeBSD.ORG Tue Jul 24 20:00:36 2012 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 6F4751065672 for ; Tue, 24 Jul 2012 20:00:36 +0000 (UTC) (envelope-from luigi@onelab2.iet.unipi.it) Received: from onelab2.iet.unipi.it (onelab2.iet.unipi.it [131.114.59.238]) by mx1.freebsd.org (Postfix) with ESMTP id 877CE8FC12 for ; Tue, 24 Jul 2012 20:00:23 +0000 (UTC) Received: by onelab2.iet.unipi.it (Postfix, from userid 275) id 3331B7300A; Tue, 24 Jul 2012 22:20:19 +0200 (CEST) Date: Tue, 24 Jul 2012 22:20:19 +0200 From: Luigi Rizzo To: current@freebsd.org Message-ID: <20120724202019.GA22927@onelab2.iet.unipi.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.3i Cc: Subject: RFC: use EM_LEGACY_IRQ in if_lem.c ? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Jul 2012 20:00:36 -0000 if_lem.c ("lem", one of the e1000 drivers) has 2 possible interrupt modes: EM_LEGACY_IRQ uses the standard dispatch mechanism, whereas FAST_INTR has a custom handler that signals a taskqueue to do the job. I have no idea which actual hardware uses it (all of my Intel 1G cards use either "em" or "igb"), but "lem" is the driver used in qemu, and there the EM_LEGACY_IRQ gives approx 10% higher packet rates than the other. Any objections if i change the default to EM_LEGACY_IRQ ? cheers luigi