From owner-cvs-src@FreeBSD.ORG Tue Sep 6 17:16:55 2005 Return-Path: X-Original-To: cvs-src@FreeBSD.org Delivered-To: cvs-src@FreeBSD.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id D03E516A41F; Tue, 6 Sep 2005 17:16:55 +0000 (GMT) (envelope-from scottl@samsco.org) Received: from pooker.samsco.org (pooker.samsco.org [168.103.85.57]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1134A43D64; Tue, 6 Sep 2005 17:16:43 +0000 (GMT) (envelope-from scottl@samsco.org) Received: from [192.168.254.11] (junior.samsco.home [192.168.254.11]) (authenticated bits=0) by pooker.samsco.org (8.13.3/8.13.3) with ESMTP id j86HGeSc024378; Tue, 6 Sep 2005 11:16:40 -0600 (MDT) (envelope-from scottl@samsco.org) Message-ID: <431DCEFB.9030005@samsco.org> Date: Tue, 06 Sep 2005 11:16:43 -0600 From: Scott Long User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.7.8) Gecko/20050615 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Nate Lawson References: <200509051602.j85G2Bpo090258@repoman.freebsd.org> <20050905094341.A23343@xorpc.icir.org> <20050905180050.GB41863@cell.sick.ru> <20050905141451.A27290@xorpc.icir.org> <20050906061828.GQ41863@cell.sick.ru> <20050906012755.B34182@xorpc.icir.org> <20050906112608.N51625@fledge.watson.org> <431DC64E.9010903@root.org> In-Reply-To: <431DC64E.9010903@root.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-2.8 required=3.8 tests=ALL_TRUSTED autolearn=failed version=3.0.2 X-Spam-Checker-Version: SpamAssassin 3.0.2 (2004-11-16) on pooker.samsco.org Cc: src-committers@FreeBSD.org, Luigi Rizzo , cvs-all@FreeBSD.org, Gleb Smirnoff , Robert Watson , cvs-src@FreeBSD.org Subject: Re: cvs commit: src/sys/kern kern_poll.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 06 Sep 2005 17:16:56 -0000 Nate Lawson wrote: > Robert Watson wrote: > >> >> On Tue, 6 Sep 2005, Luigi Rizzo wrote: >> >>> On Tue, Sep 06, 2005 at 10:18:28AM +0400, Gleb Smirnoff wrote: >>> >>>> Luigi, >>> >>> >>> ... >>> >>>> The idlepoll thread is single. >>> >>> >>> >>> ok this is very good. Re. netisr vs idlepoll, perhaps a way could be >>> to bump the idlepoll priority very high upon a net soft interrupt, >>> and drop it down to its normal value once done with the netisr cycle. >>> so we don't have to arbitrate among the two. >> >> >> Also, if we gradually move to a polling model that handles polling for >> non-network devices, it would result in a rather mixed model. One of >> the challenges of moving to a mixed polling model (one that supports >> non-network devices) is that network devices have a fairly well >> understood currency for work: processing of packets. Other devices >> may have less well understood, or at least not easily comparable, >> workloads... > > > For the case of storage, you actually have a better model since all > transactions are initiated from the host (as opposed to packet > arrivals). This gives an easy metric for a dynamic polling threshold -- > if you have a deep queue of outstanding requests and one completes, you > should poll a little more than normal. > Except for target mode. Scott