From owner-freebsd-current@FreeBSD.ORG Thu Oct 9 05:57:36 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 79B6D16A4C4 for ; Thu, 9 Oct 2003 05:57:36 -0700 (PDT) Received: from isrv.tric.tomsk.gov.ru (isrv.tric.tomsk.gov.ru [213.183.106.13]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7B7A043FB1 for ; Thu, 9 Oct 2003 05:57:32 -0700 (PDT) (envelope-from mike@tric.tomsk.gov.ru) Received: from admin (admin.sobes [192.168.8.2])h99CvOdk066715; Thu, 9 Oct 2003 19:57:24 +0700 (NOVST) (envelope-from mike@tric.tomsk.gov.ru) From: "Michael O. Boev" To: "Terry Lambert" Date: Thu, 9 Oct 2003 19:57:24 +0700 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.6604 (9.0.2911.0) In-Reply-To: <3F8535F6.36957D17@mindspring.com> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Importance: Normal X-Virus-Scanned: by amavisd-new cc: freebsd-current@FreeBSD.ORG Subject: RE: Why is em nic generating interrupts? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 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: Thu, 09 Oct 2003 12:57:36 -0000 > -----Original Message----- > From: Terry Lambert [mailto:tlambert2@mindspring.com] > Sent: Thursday, October 09, 2003 5:19 PM > To: Michael O. Boev > Cc: freebsd-current@FreeBSD.ORG > Subject: Re: Why is em nic generating interrupts? > > > "Michael O. Boev" wrote: > > I've got a [uniprocessor 5.1-RELEASE] router machine with fxp > and em nics. > > I've built my kernel with the following included: > > > > options DEVICE_POLLING > > options HZ=2500 > > > > and enabled polling in /etc/sysctl.conf. > [ ... ] > > What's happening? Is polling working in my case? > > If yes, why is vmstat showing interrupts? I see clearly, > > that fxp's counter doesn't increase, and em's is constantly growing. > > > > Is there anyone who knows for sure that em's polling works? > > You may want to ask Luigi; polling is his code. > > However, I believe the issue is that polling doesn't start > until you take an interrupt, and it stops as soon as there is > no more data to process, and waits for the next interrupt. > > If you were to jack your load way up, you would probably see > an increase in interrupts, then them dropping off dramatically. To this dare I object, that there is traffic going through this machine, and fxp0 is NOT generating interrupts, while em IS. So, if the rule above works, they both have to behave in same ways. > > If all else fails, read the source code... 8-). )) I've tried to, but... had to ask here. So all is left is to ask Luigi and Intel. > > -- Terry > -- Best wishes, [mike@tric.tomsk.gov.ru].