From owner-freebsd-fs@FreeBSD.ORG Tue Oct 9 19:31:12 2007 Return-Path: Delivered-To: freebsd-fs@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 819EB16A469; Tue, 9 Oct 2007 19:31:12 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: from mail.garage.freebsd.pl (arm132.internetdsl.tpnet.pl [83.17.198.132]) by mx1.freebsd.org (Postfix) with ESMTP id D4EEF13C4B5; Tue, 9 Oct 2007 19:31:11 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id EF4BC45EE5; Tue, 9 Oct 2007 21:31:08 +0200 (CEST) Received: from localhost (154.81.datacomsa.pl [195.34.81.154]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id 26CB545E93; Tue, 9 Oct 2007 21:31:04 +0200 (CEST) Date: Tue, 9 Oct 2007 21:30:52 +0200 From: Pawel Jakub Dawidek To: Darren Reed Message-ID: <20071009193051.GA13519@garage.freebsd.pl> References: <20071005000046.GC92272@garage.freebsd.pl> <20071008121523.GM2327@garage.freebsd.pl> <86bqb97mym.fsf@ds4.des.no> <20071008133846.GP2327@garage.freebsd.pl> <470BD649.9050505@freebsd.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Qxx1br4bt0+wmkIi" Content-Disposition: inline In-Reply-To: <470BD649.9050505@freebsd.org> User-Agent: Mutt/1.4.2.3i X-PGP-Key-URL: http://people.freebsd.org/~pjd/pjd.asc X-OS: FreeBSD 7.0-CURRENT i386 X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on mail.garage.freebsd.pl X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=BAYES_00 autolearn=ham version=3.0.4 Cc: freebsd-fs@FreeBSD.org, Dag-Erling Sm??rgrav , freebsd-current@FreeBSD.org Subject: Re: ZFS kmem_map too small. X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Oct 2007 19:31:12 -0000 --Qxx1br4bt0+wmkIi Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Oct 09, 2007 at 12:28:09PM -0700, Darren Reed wrote: > Pawel Jakub Dawidek wrote: > >... > > > >For i386 one has to set, eg. 'options KVA_PAGES=3D512' to the kernel > >config to be able to define kmem larger than ~700MB. I guess you're > >running amd64, maybe there is similar requirement? > > =20 >=20 > Given how much RAM PCs have these days, why isn't this a default for=20 > GENERIC? >=20 > Or why isn't it at least a tunable rather than an option? This may be a good reason - today's PCs have a lot of RAM and KVA_PAGES splits address space between userland and kernel - the more address space for the kernel, the less address space for the userland. KVA_PAGES=3D512 splits 4GB address space in half, so userland processes can address at most 2GB of memory. --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --Qxx1br4bt0+wmkIi Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iD8DBQFHC9brForvXbEpPzQRAq24AKDQ+OUGZ9dwkEXYyuSvKmTG7m31ogCgws3O TnfpmvNtci4dBdOmDiKPbAQ= =xv+V -----END PGP SIGNATURE----- --Qxx1br4bt0+wmkIi--