From owner-freebsd-stable@FreeBSD.ORG Tue Aug 5 17:19:36 2008 Return-Path: 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 CDD56106567E for ; Tue, 5 Aug 2008 17:19:36 +0000 (UTC) (envelope-from max@love2party.net) Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.126.183]) by mx1.freebsd.org (Postfix) with ESMTP id 6139A8FC08 for ; Tue, 5 Aug 2008 17:19:36 +0000 (UTC) (envelope-from max@love2party.net) Received: from vampire.homelinux.org (dslb-088-066-060-103.pools.arcor-ip.net [88.66.60.103]) by mrelayeu.kundenserver.de (node=mrelayeu0) with ESMTP (Nemesis) id 0MKwh2-1KQQC717Ld-0000ZI; Tue, 05 Aug 2008 19:19:35 +0200 Received: (qmail 83367 invoked from network); 5 Aug 2008 17:19:34 -0000 Received: from fbsd8.laiers.local (192.168.4.151) by ns1.laiers.local with SMTP; 5 Aug 2008 17:19:34 -0000 From: Max Laier Organization: FreeBSD To: freebsd-stable@freebsd.org Date: Tue, 5 Aug 2008 19:19:34 +0200 User-Agent: KMail/1.9.52 (FreeBSD/8.0-CURRENT; KDE/4.0.83; i386; ; ) References: <47713ee10808050839k5b258831x66bc52f70b2c355b@mail.gmail.com> In-Reply-To: <47713ee10808050839k5b258831x66bc52f70b2c355b@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200808051919.34577.max@love2party.net> X-Provags-ID: V01U2FsdGVkX18NCqhhD6n3ISxhySbPPKr4nEgbz0YQeGUvWr9 ecUcZPMsCsuxjdBYv2kXPMrrBG0vzYJQv4LA7njWCk9lcG8cW5 zR+MYvX1X/4n4GTGAkbuQ== Cc: Lin Jui-Nan Eric Subject: Re: Max size of one swap slice X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 05 Aug 2008 17:19:36 -0000 On Tuesday 05 August 2008 17:39:11 Lin Jui-Nan Eric wrote: > Recently we found that we can only allocate 32GB for one swap slice. > Does there is any sysctl oid or any kernel option to increase it? Why > we have this restriction? this is a consequence of the data structure used to manage swap space. See sys/blist.h for details. It *seems* that you *might* be able to increase the coverage by decreasing BLIST_META_RADIX, but that's from a quick glance and most certainly not a good idea. However, the blist is a abstract enough API so that you can likely replace it with something that supports 64bit addresses (and thus 512*2^64 bytes of swap space per device) ... but I don't see why you'd want to do something like this. Remember that you need memory to manage your swap space as well! -- /"\ Best regards, | mlaier@freebsd.org \ / Max Laier | ICQ #67774661 X http://pf4freebsd.love2party.net/ | mlaier@EFnet / \ ASCII Ribbon Campaign | Against HTML Mail and News