From owner-freebsd-current Thu Feb 1 11:14:37 2001 Delivered-To: freebsd-current@freebsd.org Received: from boco.fee.vutbr.cz (boco.fee.vutbr.cz [147.229.9.11]) by hub.freebsd.org (Postfix) with ESMTP id BA55B37B491 for ; Thu, 1 Feb 2001 11:14:17 -0800 (PST) Received: from kazi.dcse.fee.vutbr.cz (kazi.dcse.fee.vutbr.cz [147.229.8.12]) by boco.fee.vutbr.cz (8.11.2/8.11.2) with ESMTP id f11JEEo84506 (using TLSv1/SSLv3 with cipher EDH-RSA-DES-CBC3-SHA (168 bits) verified OK); Thu, 1 Feb 2001 20:14:14 +0100 (CET) Received: (from cejkar@localhost) by kazi.dcse.fee.vutbr.cz (8.11.0/8.11.0) id f11JED957296; Thu, 1 Feb 2001 20:14:13 +0100 (CET) Date: Thu, 1 Feb 2001 20:14:13 +0100 From: Cejka Rudolf To: Sheldon Hearn Cc: freebsd-current@freebsd.org Subject: Re: Does task scheduler work correctly? (... nice bug fix) Message-ID: <20010201201413.A55503@dcse.fee.vutbr.cz> References: <20010201192304.A54677@dcse.fee.vutbr.cz> <39485.981052345@axl.fw.uunet.co.za> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <39485.981052345@axl.fw.uunet.co.za>; from sheldonh@uunet.co.za on Thu, Feb 01, 2001 at 08:32:25PM +0200 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Sheldon Hearn wrote (2001/02/01): > What I remember of the discussions that surrounded this one, your > summary is correct. The only thing is that nice isn't so much _broken_ > as it just isn't doing what you'd expect it to. :-) Ok, scheduler in -current is not broken. But I'm afraid that in -stable it is - can (niced) process cause a lock of machine?. Currently, we have dual processor box with 4.2-STABLE and it silently locks too often. With current scheduler in mind, it is hard to say if I should search in HW or SW for a potential fix... > I don't think any of the FreeBSD manual pages suggest that nice 20 > processes aren't supposed to get _any_ CPU time. Maybe. But there are some conventions and two-process sensitivity 2.5:1 is not very big (is low). Solaris and Linux have much bigger ratio (sufficient). So why FreeBSD has to be so much different? Insensitivity of nice were problem in the past and it is going back. Users need to run some processes (!= dnetc != setiathome) enough hidden and idprio does not work either. Unfortunately, it is sufficient consideration why do not use FreeBSD for example as a general purpose server: When anybody needs to run long-time computation process, he can use only nice 20 and other users are not blind and can see, that operating system does not want to give sufficient time to their short-time computation processes. And users can force to switch to another system - just hear "but Linux do..." :-( -- Rudolf Cejka (cejkar@dcse.fee.vutbr.cz; http://www.fee.vutbr.cz/~cejkar) Brno University of Technology, Faculty of El. Engineering and Comp. Science Bozetechova 2, 612 66 Brno, Czech Republic To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message