From owner-freebsd-hackers@FreeBSD.ORG Wed Sep 1 12:21:57 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id DF27510656C4; Wed, 1 Sep 2010 12:21:57 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from mail-fx0-f54.google.com (mail-fx0-f54.google.com [209.85.161.54]) by mx1.freebsd.org (Postfix) with ESMTP id 3A1AE8FC15; Wed, 1 Sep 2010 12:21:56 +0000 (UTC) Received: by fxm4 with SMTP id 4so5409521fxm.13 for ; Wed, 01 Sep 2010 05:21:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :x-enigmail-version:content-type:content-transfer-encoding; bh=aye6magDiUeW6Xe07IAZI3Rlv93bizq39NJWsWFUHXU=; b=gNfxa7772+B5kVmqAJbuCdAK8bACnbL9uo6AoJWd/U5zyOJpSz3vvMvsHD2wxrHNF7 iq5fdPViCLikpeSavkr1Vk/3uvx/qsrjUnG9/00rqJU8hKLVJA4WDOvWNE5nspMDFutx TF+YhyXNQHuQRTIpJ1orn3+T9GbYwuOZHmM74= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=s85COAQpaSzIm17ZwoVhKSxAbORpx8Dt0kSeGnlJNcDx8Gd7vIuQmXyAacBGhu2qss uCE1itGoFtzFUDLRfLrKrxXLgyMKWpuPwilUoF/X+5yi0gw7ALwg3vMSEM9G596JpGOE 0ZJfnceu7LcEY5cmPzIa8+QXa5OCQFlITwP3M= Received: by 10.223.105.132 with SMTP id t4mr6815056fao.75.1283343716237; Wed, 01 Sep 2010 05:21:56 -0700 (PDT) Received: from mavbook.mavhome.dp.ua (pc.mavhome.dp.ua [212.86.226.226]) by mx.google.com with ESMTPS id u8sm4538230fah.36.2010.09.01.05.21.54 (version=SSLv3 cipher=RC4-MD5); Wed, 01 Sep 2010 05:21:55 -0700 (PDT) Sender: Alexander Motin Message-ID: <4C7E4555.3000802@FreeBSD.org> Date: Wed, 01 Sep 2010 15:21:41 +0300 From: Alexander Motin User-Agent: Thunderbird 2.0.0.24 (X11/20100402) MIME-Version: 1.0 To: gljennjohn@googlemail.com References: <4C7A5C28.1090904@FreeBSD.org> <20100830110932.23425932@ernst.jennejohn.org> <4C7B82EA.2040104@FreeBSD.org> <20100830121148.11926306@ernst.jennejohn.org> <20100831102918.4f5404cc@ernst.jennejohn.org> <4C7CC1DE.1080907@FreeBSD.org> <4C7E2E8A.3030709@FreeBSD.org> <20100901141541.3e36c868@ernst.jennejohn.org> In-Reply-To: <20100901141541.3e36c868@ernst.jennejohn.org> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-hackers@freebsd.org, FreeBSD-Current Subject: Re: One-shot-oriented event timers management X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Sep 2010 12:21:58 -0000 Gary Jennejohn wrote: > On Wed, 01 Sep 2010 13:44:26 +0300 > Alexander Motin wrote: >> I have reproduced the problem locally. It happens more often when ticks >> are not stopped on idle, like in your original case (or if explicitly >> enabled by kern.eventtimer.idletick sysctl). >> >> I've made some changes to HPET driver, which, I hope, should fix >> interrupt losses there. >> >> Updated patch: http://people.freebsd.org/~mav/timers_oneshot6.patch >> >> Patch also includes some optimizations to reduce lock contention. >> >> Thanks for testing. > > OK, I'll give it a try, althought your previous patch seems to be working > quite well. Stopping/starting timer around idle could partially hide the problem. Single external even in such case could be enough to revive system. > BTW I've also been using tm6292_idle.patch. Do I really need it? It is not necessary. It just reduces number of events generated by system by hacking several aggressive places I've found. -- Alexander Motin