From owner-freebsd-fs Wed Nov 13 6:28:58 2002 Delivered-To: freebsd-fs@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7F93137B401 for ; Wed, 13 Nov 2002 06:28:57 -0800 (PST) Received: from pohoda.cz (pohoda.pohoda.cz [194.228.111.151]) by mx1.FreeBSD.org (Postfix) with SMTP id C2FA643E88 for ; Wed, 13 Nov 2002 06:28:54 -0800 (PST) (envelope-from plusik@pohoda.cz) Received: (qmail 21586 invoked from network); 13 Nov 2002 13:41:26 -0000 Received: from plusik@pohoda.cz by pohoda.cz by uid 500 with qmail-scanner-1.15 ( Clear:. Processed in 0.050461 secs); 13 lis 2002 13:41:26 -0000 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 13 Nov 2002 13:41:26 -0000 Date: Wed, 13 Nov 2002 14:41:26 +0100 (CET) From: Tomas Pluskal To: Bruce Evans Cc: Terry Lambert , Subject: Re: seeking help to rewrite the msdos filesystem Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org > The problem here seems to be just that some drives don't have any > significant buffering and/or have huge command overheads, so even the > ffs default block size of 16K is too small. The msdosfs default block > size of 2K for ZIP drives is far too small. Clustering increases the > effective block size to 64K, which is large enough for most purposes, > but mdosfs is missing the few lines of code needed to implement > clustering, and read-ahead doesn't help since it is done in units of > the too-small block size. This is an old problem, but mostly finished > going away about 7 years when adequate buffering and/or firmware to > manage it became normal in all ordinary disk drives. Could you please write a liitle more about those "missing few lines of code" ? I think it is what I could do and what would help when using ZIP drives and digital cameras etc.. Thanks Tomas Pluskal To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message