From owner-freebsd-stable@freebsd.org Sat Apr 7 15:13:42 2018 Return-Path: Delivered-To: freebsd-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 0879BF8FFFC for ; Sat, 7 Apr 2018 15:13:42 +0000 (UTC) (envelope-from li-fbsd@citylink.dinoex.sub.org) Received: from uucp.dinoex.sub.de (uucp.dinoex.sub.de [IPv6:2001:1440:5001:1::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "uucp.dinoex.sub.de", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4F33179344 for ; Sat, 7 Apr 2018 15:13:41 +0000 (UTC) (envelope-from li-fbsd@citylink.dinoex.sub.org) Received: from uucp.dinoex.sub.de (uucp.dinoex.sub.de [194.45.71.2]) by uucp.dinoex.sub.de (8.15.2/8.15.2) with ESMTPS id w37FDBAj066511 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Sat, 7 Apr 2018 17:13:11 +0200 (CEST) (envelope-from li-fbsd@citylink.dinoex.sub.org) X-MDaemon-Deliver-To: Received: from citylink.dinoex.sub.org (uucp@localhost) by uucp.dinoex.sub.de (8.15.2/8.15.2/Submit) with UUCP id w37FDBa9066510 for freebsd-stable@FreeBSD.ORG; Sat, 7 Apr 2018 17:13:11 +0200 (CEST) (envelope-from li-fbsd@citylink.dinoex.sub.org) Received: from gate.oper.dinoex.org (gate-e [192.168.98.2]) by citylink.dinoex.sub.de (8.15.2/8.15.2) with ESMTP id w37Ebct4034900 for ; Sat, 7 Apr 2018 16:37:39 +0200 (CEST) (envelope-from li-fbsd@citylink.dinoex.sub.org) Received: from gate.oper.dinoex.org (gate-e [192.168.98.2]) by gate.oper.dinoex.org (8.15.2/8.15.2) with ESMTP id w37EYcQX034402 for ; Sat, 7 Apr 2018 16:34:38 +0200 (CEST) (envelope-from li-fbsd@citylink.dinoex.sub.org) Received: (from news@localhost) by gate.oper.dinoex.org (8.15.2/8.15.2/Submit) id w37EYcHK034391 for freebsd-stable@FreeBSD.ORG; Sat, 7 Apr 2018 16:34:38 +0200 (CEST) (envelope-from li-fbsd@citylink.dinoex.sub.org) X-Authentication-Warning: gate.oper.dinoex.org: news set sender to li-fbsd@citylink.dinoex.sub.org using -f From: Peter Subject: Re: kern.sched.quantum: Creepy, sadistic scheduler Date: Sat, 7 Apr 2018 16:21:25 +0200 Organization: even some more stinky socks Message-ID: References: <9FDC510B-49D0-4722-B695-6CD38CA20D4A@gmail.com> <8cfdb8a3-86a0-17ba-1e41-ff1912a30ee9@m5p.com> <2d3dfb30-fb34-55e4-0572-df17ceb5f66e@freebsd.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Info: oper.dinoex.de; logging-data="32143"; mail-complaints-to="usenet@citylink.dinoex.sub.org" User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:51.0) Gecko/20100101 Firefox/51.0 SeaMonkey/2.48 In-Reply-To: <2d3dfb30-fb34-55e4-0572-df17ceb5f66e@freebsd.org> Sender: li-fbsd@citylink.dinoex.sub.org To: freebsd-stable@FreeBSD.ORG X-Milter: Spamilter (Reciever: uucp.dinoex.sub.de; Sender-ip: 194.45.71.2; Sender-helo: uucp.dinoex.sub.de; ) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (uucp.dinoex.sub.de [194.45.71.2]); Sat, 07 Apr 2018 17:13:12 +0200 (CEST) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 07 Apr 2018 15:13:42 -0000 Julian Elischer wrote: > for a single CPU you really should compile a kernel with SMP turned off > and 4BSD scheduler. > > ULE is just trying too hard to do stuff you don't need. Julian, if we agree on this, I am fine. (This implies that SCHED_4BSD will *not* be retired for an indefinite time!) I tested yesterday, and SCHED_4BSD doesn't show the annoying behaviour. SMP seems to be no problem (and I need that), but PREEMPTION is definitely related to the problem (see my other message sent now). P.