From owner-freebsd-current@FreeBSD.ORG Fri Jan 14 18:01:02 2011 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 96E951065672; Fri, 14 Jan 2011 18:01:02 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 695E18FC1D; Fri, 14 Jan 2011 18:01:02 +0000 (UTC) Received: from bigwig.baldwin.cx (66.111.2.69.static.nyinternet.net [66.111.2.69]) by cyrus.watson.org (Postfix) with ESMTPSA id 0947846B52; Fri, 14 Jan 2011 13:01:02 -0500 (EST) Received: from jhbbsd.localnet (smtp.hudson-trading.com [209.249.190.9]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 025F58A009; Fri, 14 Jan 2011 13:01:01 -0500 (EST) From: John Baldwin To: Daniel Eischen Date: Fri, 14 Jan 2011 13:00:28 -0500 User-Agent: KMail/1.13.5 (FreeBSD/7.4-CBSD-20110107; KDE/4.4.5; amd64; ; ) References: <201101141211.11674.jhb@freebsd.org> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201101141300.28684.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.6 (bigwig.baldwin.cx); Fri, 14 Jan 2011 13:01:01 -0500 (EST) X-Virus-Scanned: clamav-milter 0.96.3 at bigwig.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-1.9 required=4.2 tests=BAYES_00 autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on bigwig.baldwin.cx Cc: current@freebsd.org Subject: Re: HEADSUP: Realtime thread scheduling changed 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: Fri, 14 Jan 2011 18:01:02 -0000 On Friday, January 14, 2011 12:22:18 pm Daniel Eischen wrote: > On Fri, 14 Jan 2011, John Baldwin wrote: > > > This is just a heads up that I've committed some changes to how the scheduler > > handles realtime thread priorities. Please let me know of any issues you > > encounter with nice, rtprio, or idprio. Note that as a result of these > > changes, rtprio threads will no longer share priorities with interactive > > timeshare threads. Instead, rtprio threads are now always more important than > > non-rt threads. > > Cool - thanks for doing this! Is this something that could > be MFC'able to 8? That's a harder question. This changes the effective value of the P* priority constants passed to *sleep(). That would be an ABI change for kernel modules. We could either 1) decide that it is an ABI change worth making (probably doubtful since it is mostly a new feature rather than a major bug fix) or 2) maybe MFC it but make the different priority ranges be subject to some global kernel config option. 2) isn't super ideal since you have to really make sure kernel modules are compiled with the same setting for that option to avoid weird behavior. I will MFC all the other changes I've made prior to this in which case this change would be the only local patch someone would need to have this. -- John Baldwin