From owner-freebsd-questions Thu Nov 21 4:13:38 2002 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 4F72F37B401 for ; Thu, 21 Nov 2002 04:13:36 -0800 (PST) Received: from mail.duth.gr (mail.duth.gr [192.108.114.110]) by mx1.FreeBSD.org (Postfix) with ESMTP id A03C143E6E for ; Thu, 21 Nov 2002 04:13:32 -0800 (PST) (envelope-from bigbrother@bonbon.net) Received: from bigb3server.bbcluster.gr (b9-149.xan.duth.gr [193.92.211.149]) by mail.duth.gr (8.12.6/8.12.6) with ESMTP id gALCDI0k015812 (version=TLSv1/SSLv3 cipher=EDH-DSS-DES-CBC3-SHA bits=168 verify=NO) for ; Thu, 21 Nov 2002 14:13:19 +0200 (EET) (envelope-from bigbrother@bonbon.net) Received: from bigb3server.bbcluster.gr (localhost.bbcluster.gr [127.0.0.1]) by bigb3server.bbcluster.gr (8.12.3/8.12.3) with ESMTP id gALCDDqe086558 for ; Thu, 21 Nov 2002 14:13:13 +0200 (EET) (envelope-from bigbrother@bonbon.net) Received: from localhost (bigbrother@localhost) by bigb3server.bbcluster.gr (8.12.3/8.12.3/Submit) with ESMTP id gALCDBK0086555 for ; Thu, 21 Nov 2002 14:13:13 +0200 (EET) X-Authentication-Warning: bigb3server.bbcluster.gr: bigbrother owned process doing -bs Date: Thu, 21 Nov 2002 14:13:08 +0200 (EET) From: "BigBrother (BigB3)" X-X-Sender: bigbrother@bigb3server.bbcluster.gr To: freebsd-questions@freebsd.org Subject: Performance degration of moving FFS hdd from a slow to a fast pc. Message-ID: <20021121140035.E29240-100000@bigb3server.bbcluster.gr> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I have a question about FFS filesystem. According to a paper about the design of UFS filesystem[1], if you create the FFS filesystem on a slow cpu and then move it to a fast cpu with a fast controller, theh the FFS wont perform efficient. This is justified because when the UFS is created having in mind the speed of the system, in order to create the cyllinder group summary information with optimal rotationally blocks [see page 7 of the paper]. If somebody takes the hdd of the slow pc and put it on a much faster pc, then it is reported that the throughput will drop significantly because of lost disk revolutions. I would like to know if this is true. Can I move my hdd of my old slow pc [intel 486] to a pentium III 600Mhz machine without performance penatly, or its better to re-create the filesystem? Thank you very much... References: [1] http://citeseer.nj.nec.com/mckusick84fast.html - --- We are being monitored..but there is a solution... Use PGP for signing and encrypting emails!!!! Download my public key at http://www.us.pgp.net -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.0 (FreeBSD) iD8DBQE93M3XGe/V3CxAyHoRAtCKAJsFEPJAEgYOzE8NkszHO5jUBETrnwCfTC+V vLYTHw2fXGYPIwfuzA3TitM= =/4V2 -----END PGP SIGNATURE----- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message