From owner-freebsd-geom@FreeBSD.ORG Tue Jul 31 11:46:48 2007 Return-Path: Delivered-To: geom@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 40B4616A418 for ; Tue, 31 Jul 2007 11:46:48 +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 CC31E13C45D for ; Tue, 31 Jul 2007 11:46:47 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id 2179A487F7; Tue, 31 Jul 2007 13:46:46 +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 BD599487F5; Tue, 31 Jul 2007 13:46:41 +0200 (CEST) Date: Tue, 31 Jul 2007 13:45:56 +0200 From: Pawel Jakub Dawidek To: Fluffles Message-ID: <20070731114555.GQ1092@garage.freebsd.pl> References: <46AA50B4.9080901@fluffles.net> <20070727210032.0140413C457@mx1.freebsd.org> <20070730192654.GO1092@garage.freebsd.pl> <46AE4B94.8010107@fluffles.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/d7X7C0hV/blnKmH" Content-Disposition: inline In-Reply-To: <46AE4B94.8010107@fluffles.net> 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: geom@FreeBSD.org, Dominic Bishop Subject: Re: Increasing GELI performance X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 31 Jul 2007 11:46:48 -0000 --/d7X7C0hV/blnKmH Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jul 30, 2007 at 10:35:32PM +0200, Fluffles wrote: > Pawel Jakub Dawidek wrote: > >No matter how many cores/cpus you have if you run single-threaded > >application. What you do exactly is: > >1. Send read of 128kB. > >2. One of geli threads picks it up, decrypts and sends it back. > >3. Send next read of 128kB. > >4. One of geli threads picks it up, decrypts and sends it back. > >... > > > >All threads will be used when there are more threads accessing provider. > > =20 >=20 > But isn't it true that the UFS filesystem utilizes read-ahead and with=20 > that a multiple I/O queue depth (somewhere between 7 to 9 queued I/O's)= =20 > - even when using something like dd to sequentially read a file on a=20 > mounted filesystem ? Then this read-ahead will cause multiple I/O=20 > request coming in and geom_eli can use multiple threads to maximize I/O= =20 > throughput. Maybe Dominic can try playing with the "vfs.read_max" sysctl= =20 > variable. You are right in general, but if you reread e-mail I was answering to, you will see that the author was reading from/writing to GEOM provider, not file system. --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --/d7X7C0hV/blnKmH Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iD8DBQFGryDzForvXbEpPzQRAgjpAKCMxdqXm0qNVI58S0TzWhusIsJoLwCaAy6P GUF5MHF9O83N+6ieA2Yo/N4= =rcFt -----END PGP SIGNATURE----- --/d7X7C0hV/blnKmH--