From owner-freebsd-current@FreeBSD.ORG  Sat Nov 20 01:16:41 2010
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 01197106564A
	for <freebsd-current@freebsd.org>; Sat, 20 Nov 2010 01:16:41 +0000 (UTC)
	(envelope-from freebsd-current@m.gmane.org)
Received: from lo.gmane.org (lo.gmane.org [80.91.229.12])
	by mx1.freebsd.org (Postfix) with ESMTP id A5F0A8FC0C
	for <freebsd-current@freebsd.org>; Sat, 20 Nov 2010 01:16:40 +0000 (UTC)
Received: from list by lo.gmane.org with local (Exim 4.69)
	(envelope-from <freebsd-current@m.gmane.org>) id 1PJc4F-0004Pi-L2
	for freebsd-current@freebsd.org; Sat, 20 Nov 2010 02:16:39 +0100
Received: from cpe-188-129-101-155.dynamic.amis.hr ([188.129.101.155])
	by main.gmane.org with esmtp (Gmexim 0.1 (Debian))
	id 1AlnuQ-0007hv-00
	for <freebsd-current@freebsd.org>; Sat, 20 Nov 2010 02:16:39 +0100
Received: from ivoras by cpe-188-129-101-155.dynamic.amis.hr with local
	(Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00
	for <freebsd-current@freebsd.org>; Sat, 20 Nov 2010 02:16:39 +0100
X-Injected-Via-Gmane: http://gmane.org/
To: freebsd-current@freebsd.org
From: Ivan Voras <ivoras@freebsd.org>
Date: Sat, 20 Nov 2010 02:16:24 +0100
Lines: 37
Message-ID: <ic77h9$39d$1@dough.gmane.org>
References: <AANLkTinHSX1+s3hrHyDeU2Vfp6zekTe04XkHhTc2jtLv@mail.gmail.com>	<4CE50849.106@zedat.fu-berlin.de>
	<4CE52177.3020306@freebsd.org>	<AANLkTimq=5KJb5AGA6H0yA7AWrp+HZMRhfH6pnh=_NqA@mail.gmail.com>	<4CE58CD8.2000407@mail.zedat.fu-berlin.de>
	<20101120004955.68c8af6a.taku@tackymt.homeip.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
X-Complaints-To: usenet@dough.gmane.org
X-Gmane-NNTP-Posting-Host: cpe-188-129-101-155.dynamic.amis.hr
User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US;
	rv:1.9.2.12) Gecko/20101102 Thunderbird/3.1.6
In-Reply-To: <20101120004955.68c8af6a.taku@tackymt.homeip.net>
Cc: freebsd-performance@freebsd.org, freebsd-stable@freebsd.org
Subject: Re: TTY task group scheduling
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 20 Nov 2010 01:16:41 -0000

On 11/19/10 16:49, Taku YAMAMOTO wrote:

> I have a dumb local hack to grant ts_slice proportional to the duration
> the waking thread slept rather than unconditionally reset to sched_slice.
>
>
> --- sys/kern/sched_ule.c.orig
> +++ sys/kern/sched_ule.c
> @@ -1928,12 +1928,16 @@ sched_wakeup(struct thread *td)
>   		u_int hzticks;
>
>   		hzticks = (ticks - slptick)<<  SCHED_TICK_SHIFT;
> +		if (hzticks>  SCHED_SLP_RUN_MAX)
> +			hzticks = SCHED_SLP_RUN_MAX;
>   		ts->ts_slptime += hzticks;
> +		/* Grant additional slices after we sleep. */
> +		ts->ts_slice += hzticks / tickincr;
> +		if (ts->ts_slice > sched_slice)
> +			ts->ts_slice = sched_slice;

If I read it correctly, now instead of the slice given to the thread 
being always sched_slice, now it is reduced to a value smaller than 
sched_slice based on how long did the thread sleep?

How does that help?

>   		sched_interact_update(td);
>   		sched_pctcpu_update(ts);
>   	}
> -	/* Reset the slice value after we sleep. */
> -	ts->ts_slice = sched_slice;
>   	sched_add(td, SRQ_BORING);
>   }
>
>
>