From owner-freebsd-stable@FreeBSD.ORG Thu Mar 30 00:11:50 2006 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B999E16A401 for ; Thu, 30 Mar 2006 00:11:50 +0000 (UTC) (envelope-from chrcoluk@gmail.com) Received: from pproxy.gmail.com (pproxy.gmail.com [64.233.166.181]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8D53143D45 for ; Thu, 30 Mar 2006 00:11:49 +0000 (GMT) (envelope-from chrcoluk@gmail.com) Received: by pproxy.gmail.com with SMTP id b36so103945pyb for ; Wed, 29 Mar 2006 16:11:48 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=f4GS5zbHCuxqACr1Ho867063/58kD3dzYGjbf5sGKocEAfFMZxDCLk+z4d2jvZjTURdQ8X3A2xRIZe0h/wgHxGvZGbp69S3uwvm44VkfLVuBI6b21SFm9iZmIMvlDJwwCVMWojjwjvw9fm6BAirpK+bz9qxuClRl72B8oi0qj7Q= Received: by 10.35.76.9 with SMTP id d9mr1930118pyl; Wed, 29 Mar 2006 11:52:36 -0800 (PST) Received: by 10.35.36.18 with HTTP; Wed, 29 Mar 2006 11:52:36 -0800 (PST) Message-ID: <3aaaa3a0603291152g2ea1fcbdo57342e3031882060@mail.gmail.com> Date: Wed, 29 Mar 2006 20:52:36 +0100 From: Chris To: "Robert Watson" In-Reply-To: <20060329175256.W19236@fledge.watson.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <3aaaa3a0603281134sd0d4e16x@mail.gmail.com> <20060329030459.40be9cb2.conrads@cox.net> <861wwlcsnj.fsf@xps.des.no> <20060329175256.W19236@fledge.watson.org> Cc: =?ISO-8859-1?Q?Dag-Erling_Sm=F8rgrav?= , "Conrad J. Sabatier" , freebsd-stable@freebsd.org, bmilekic@freebsd.org Subject: Re: nmbclusters 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: Thu, 30 Mar 2006 00:11:50 -0000 On 29/03/06, Robert Watson wrote: > > On Wed, 29 Mar 2006, Dag-Erling Sm=F8rgrav wrote: > > > "Conrad J. Sabatier" writes: > >> Chris wrote: > >>> so [kern.ipc.nmbclusters] has no affect, has this become a read only > >>> tunable again only settable in loader.conf? > >> To the best of my knowledge, this has *always* been a loader tunable, > >> not configurable on-the-fly. > > > > kern.ipc.nmbclusters is normally computed at boot time. A compile- tim= e > > option to override it was introduced in 2.0-CURRENT. At that time, it = was > > defined in param.c. A read-only sysctl was introduced in 3.0-CURRENT. = It > > moved from param.c to uipc_mbuf.c in 4.0-CURRENT, then to subr_mbuf.c w= hen > > mballoc was introduced in 5.0-CURRENT; became a tunable at some point a= fter > > that; then moved again to kern_mbuf.c when mballoc was replaced with mb= uma > > in 6.0-CURRENT. That is the point where it became read-write, for no g= ood > > reason that I can see; setting it at runtime has no effect, because the= size > > of the mbuf zone is determined at boot time. Perhaps Bosko (who wrote = both > > mballoc and mbuma, IIRC) knows. > > Paul Saab from Yahoo! has a set of patches that allow run-time nmbcluster= s > changes to be implemented -- while it won't cause the freeing of clusters > referenced, it goes through and recalculates dependent variables, propaga= tes > them into UMA, etc. I believe they're running with this patch on 6.x, an= d I > expect that they will be merged to -CURRENT and -STABLE in the relatively= near > future. Not before 6.1, however. > > If the nmbclusters setting really has no effect right now, we should mark= the > sysctl as read-only to make it more clear it doesn't, since allowing it t= o be > set without taking effect is counter-intuitive. > > Robert N M Watson > thanks for everyones responses. My 5.4 servers seem to accept the tunable been changed at runtime although this could be a bug and it isnt really changing? 4.x I know was a boot only tunable. I have tested this now in loader.conf and it works so it seems its a minor bug where the error message is replaced by a false success output. Chris