From owner-freebsd-stable@FreeBSD.ORG  Sat Feb 28 22:31:07 2009
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
Delivered-To: freebsd-stable@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 003A5106564A
	for <freebsd-stable@freebsd.org>; Sat, 28 Feb 2009 22:31:06 +0000 (UTC)
	(envelope-from petefrench@ticketswitch.com)
Received: from constantine.ticketswitch.com (constantine.ticketswitch.com
	[IPv6:2002:57e0:1d4e:1::3])
	by mx1.freebsd.org (Postfix) with ESMTP id BA3638FC21
	for <freebsd-stable@freebsd.org>; Sat, 28 Feb 2009 22:31:06 +0000 (UTC)
	(envelope-from petefrench@ticketswitch.com)
Received: from dilbert.rattatosk ([10.64.50.6] helo=dilbert.ticketswitch.com)
	by constantine.ticketswitch.com with esmtps (TLSv1:AES256-SHA:256)
	(Exim 4.69 (FreeBSD)) (envelope-from <petefrench@ticketswitch.com>)
	id 1LdXhu-000MI9-CY
	for freebsd-stable@freebsd.org; Sat, 28 Feb 2009 22:30:54 +0000
Received: from petefrench by dilbert.ticketswitch.com with local (Exim 4.69
	(FreeBSD)) (envelope-from <petefrench@ticketswitch.com>)
	id 1LdXhu-0007nK-8N
	for freebsd-stable@freebsd.org; Sat, 28 Feb 2009 22:30:54 +0000
To: freebsd-stable@freebsd.org
Message-Id: <E1LdXhu-0007nK-8N@dilbert.ticketswitch.com>
From: Pete French <petefrench@ticketswitch.com>
Date: Sat, 28 Feb 2009 22:30:54 +0000
Subject: vm_thread_new: kstack allocation failed with vm.kmem_size="1536M"
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Production branch of FreeBSD source code <freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>, 
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 28 Feb 2009 22:31:07 -0000

So, I have a farm of machines runnign 7.1/amd64, all of which have 16 gig of
memory in them. This afternoon, as an experiment, I altered loader.conf
to have these two lines in it:

vm.kmem_size="1536M"
vm.kmem_size_max="1536M"

This is what I do on machines running ZFS - these machines are not, however
running ZFS, and do not have the zfs module loaded. I just wanted to see if
they would run OK with those kernel settings (as I may put ZFS on them in
the future)

I expected it to run fine, I just wanted to make sure. But after about
an hour I started getting the message in the subject line, and the
machines were unable to fork and needed to be reset.

Explanation anyone ? This makes no sense to me - I have actually expanded
the amount of memory available, so why is it now running out of stack
space ?! The machines are running a very simple setup of apache, mysql
and tomcat - and this runs fine with the kernel variables set as default.

I am very puzzled.

-pete.