From owner-freebsd-current@FreeBSD.ORG Wed Apr 2 20:16:00 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 3602837B401 for ; Wed, 2 Apr 2003 20:16:00 -0800 (PST) Received: from mail.chesapeake.net (chesapeake.net [205.130.220.14]) by mx1.FreeBSD.org (Postfix) with ESMTP id 6462243F3F for ; Wed, 2 Apr 2003 20:15:59 -0800 (PST) (envelope-from jroberson@chesapeake.net) Received: from localhost (jroberson@localhost) by mail.chesapeake.net (8.11.6/8.11.6) with ESMTP id h334FtW44043; Wed, 2 Apr 2003 23:15:55 -0500 (EST) (envelope-from jroberson@chesapeake.net) Date: Wed, 2 Apr 2003 23:15:55 -0500 (EST) From: Jeff Roberson To: Bruce Evans In-Reply-To: <20030403132059.V29067@gamplex.bde.org> Message-ID: <20030402231142.I64602-100000@mail.chesapeake.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: current@freebsd.org Subject: Re: ULE nice behavior fixed. 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, 03 Apr 2003 04:16:00 -0000 On Thu, 3 Apr 2003, Bruce Evans wrote: > On Wed, 2 Apr 2003, Jeff Roberson wrote: > > > On Wed, 2 Apr 2003, Bruce Evans wrote: > > > ... The scaling of niceness was re-broken in -current about 3 > > > years ago to "fix" the priority inversion problems. This is with > > > SCHED_4BSD. SCHED_ULE has larger problems. > > > > Do you know of any problem other than idlepri breakage? I just fixed > > that. I'm about to get on a plane so I don't have time to benchmark it. > > If you have a chance I'd love to see how the most recent fixes effect your > > buildworld time. > > Nothing very important. Many scheduler-related fields shown by ps are > now useless since they only have a dummy entry in them. IIRC, one is > worse than useless since the dummy entry doesn't fit in the field width. > Ah, right, you're talking about the weighted cpu? Some of these corners need to be cleaned up. I wanted to get other behavior cleaned up first. What is your impression of ULE? What do you think would be required for it to become the default scheduler? I mean, other than lots of time and benchmarking to prove it. I need to work on the cpu rebalancing code a bit more. I also want to do a fuzzy rescheduling mode that will notice how many interactive threads there are and mi_switch less agressively if there are none. My measurements show that this could have a huge perf impact on some workloads. Cheers, Jeff