From owner-freebsd-hackers Sat Jun 1 16:15:57 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id QAA09213 for hackers-outgoing; Sat, 1 Jun 1996 16:15:57 -0700 (PDT) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.211]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id QAA09196 for ; Sat, 1 Jun 1996 16:15:54 -0700 (PDT) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id QAA22365; Sat, 1 Jun 1996 16:11:39 -0700 From: Terry Lambert Message-Id: <199606012311.QAA22365@phaeton.artisoft.com> Subject: Re: Breaking ffs - speed enhancement? To: hdalog@zipnet.net Date: Sat, 1 Jun 1996 16:11:38 -0700 (MST) Cc: bde@zeta.org.au, dufault@hda.zipnet.net, hackers@FreeBSD.ORG, terry@lambert.org In-Reply-To: <199606011705.NAA10369@hda> from "Peter Dufault" at Jun 1, 96 01:05:19 pm X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk > > You would still have to keep the update marks somewhere :-). They > > should compress very well since they are only 1 bit to begin with > > and have a steady state value of 1 :-). > > You need update marks, but if you don't need to change them from > marks to time stamps when the files are closed you reduce the > overhead of a file system full of many small files being thrashed > open and closed. No, I haven't thought through the benefits and > drawbacks - I'll shutup. Don't do that. 8-). The problem is not that the semantics require the conversion, but that the conversion, using the current cache schema, requires more writes than you would want it to require. If you can increase cache locality, you can reduce the writes without giving up the semantics. Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.