From owner-freebsd-threads@FreeBSD.ORG  Fri Aug  1 00:55:01 2003
Return-Path: <owner-freebsd-threads@FreeBSD.ORG>
Delivered-To: freebsd-threads@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP
	id 1FB1237B401; Fri,  1 Aug 2003 00:55:01 -0700 (PDT)
Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21])
	by mx1.FreeBSD.org (Postfix) with ESMTP
	id A966243F93; Fri,  1 Aug 2003 00:55:00 -0700 (PDT)
	(envelope-from davidxu@FreeBSD.org)
Received: from localhost (davidxu@localhost [127.0.0.1])
	by freefall.freebsd.org (8.12.9/8.12.9) with ESMTP id h717suUp072767;
	Fri, 1 Aug 2003 00:54:58 -0700 (PDT)
	(envelope-from davidxu@FreeBSD.org)
From: David Xu <davidxu@FreeBSD.org>
To: tejun@aratech.co.kr, TeJun Huh <tj@atj.dyndns.org>,
	freebsd-threads@FreeBSD.org
Date: Fri, 1 Aug 2003 15:57:59 +0800
User-Agent: KMail/1.5.2
References: <Pine.BSF.4.21.0307312305410.27751-100000@InterJet.elischer.org>
	<Pine.GSO.4.10.10308010251180.3123-100000@pcnet5.pcnet.com>
	<20030801071835.GA2653@atj.dyndns.org>
In-Reply-To: <20030801071835.GA2653@atj.dyndns.org>
MIME-Version: 1.0
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200308011557.59484.davidxu@FreeBSD.org>
Subject: Re: And problems regarding -lthr (1:1 KSE)
X-BeenThere: freebsd-threads@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
Reply-To: davidxu@FreeBSD.org
List-Id: Threading on FreeBSD <freebsd-threads.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-threads>,
	<mailto:freebsd-threads-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-threads>
List-Post: <mailto:freebsd-threads@freebsd.org>
List-Help: <mailto:freebsd-threads-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-threads>,
	<mailto:freebsd-threads-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 01 Aug 2003 07:55:01 -0000

On Friday 01 August 2003 15:18, TeJun Huh wrote:
>  2. On M:N KSE, how to put more KSEs into one process or KSE group.
> From what I understand, a KSE multiplexes userthreads, but when the
> user thread invokes a blocking systemcall, the KSE blocks handling it
> and another KSE does an upcall to user level scheduler notifying the
> blocking and the user level scheduler can utilize the upcalling KSE to
> run another user thread, thus maintaining concurrency.  (Am I getting
> it right?)
>
>  So, with large number of threads blocked, large number of KSEs are
> needed and, from what I've read, the hard limit will be ~9000 because
> KSEs shouldn't be very different from kernel threads from this
> perspective.  But what I get is something around 150 and wanna know if
> there is any sysctl or boot kernel parameter or anything that can be
> tuned to increase this limit.
>
The following sysctls may help you:
max contextes can be blocked in kernel(not limited by LDT):

kern.threads.max_threads_per_proc

max system scope thread can be created(limited by LDT):
kern.threads.max_groups_per_proc


>  3. Lastly, about the kernel hang problem.  Is it a known bug or fixed
> in 5.1-CURRENT?  If not, I think this is a very serious problem, because
> any user can hang the whole system very hard.
>

After 5.1 release, there are much improvements had been commited.

>  Thanks in advance.
> _______________________________________________
> freebsd-threads@freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-threads
> To unsubscribe, send any mail to "freebsd-threads-unsubscribe@freebsd.org"

David Xu