From owner-freebsd-hackers@FreeBSD.ORG  Fri Feb 22 19:12:57 2013
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@FreeBSD.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by hub.freebsd.org (Postfix) with ESMTP id 98BBA3D0
 for <freebsd-hackers@FreeBSD.org>; Fri, 22 Feb 2013 19:12:57 +0000 (UTC)
 (envelope-from ian@FreeBSD.org)
Received: from duck.symmetricom.us (duck.symmetricom.us [206.168.13.214])
 by mx1.freebsd.org (Postfix) with ESMTP id 596273FA
 for <freebsd-hackers@FreeBSD.org>; Fri, 22 Feb 2013 19:12:57 +0000 (UTC)
Received: from damnhippie.dyndns.org (daffy.symmetricom.us [206.168.13.218])
 by duck.symmetricom.us (8.14.6/8.14.6) with ESMTP id r1MJCuUp064241
 for <freebsd-hackers@FreeBSD.org>; Fri, 22 Feb 2013 12:12:56 -0700 (MST)
 (envelope-from ian@FreeBSD.org)
Received: from [172.22.42.240] (revolution.hippie.lan [172.22.42.240])
 by damnhippie.dyndns.org (8.14.3/8.14.3) with ESMTP id r1MJCsli054826
 for <freebsd-hackers@freebsd.org>; Fri, 22 Feb 2013 12:12:54 -0700 (MST)
 (envelope-from ian@FreeBSD.org)
Subject: why no per-thread scheduling niceness?
From: Ian Lepore <ian@FreeBSD.org>
To: "freebsd-hackers@freebsd.org" <freebsd-hackers@FreeBSD.org>
Content-Type: text/plain; charset="us-ascii"
Date: Fri, 22 Feb 2013 12:12:54 -0700
Message-ID: <1361560374.1185.85.camel@revolution.hippie.lan>
Mime-Version: 1.0
X-Mailer: Evolution 2.32.1 FreeBSD GNOME Team Port 
Content-Transfer-Encoding: 7bit
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.14
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
 <freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-hackers>, 
 <mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
 <mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 22 Feb 2013 19:12:57 -0000

I'm curious why the concept of scheduling niceness applies only to an
entire process, and it's not possible to have nice threads within a
process.  Is there any fundamental reason why it couldn't be supported
with some extra bookkeeping to track niceness per thread?

-- Ian