From owner-freebsd-hackers Tue Apr 4 10:30:41 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id KAA15678 for hackers-outgoing; Tue, 4 Apr 1995 10:30:41 -0700 Received: from linux4nn.iaf.nl (root@linux4nn.iaf.nl [193.67.144.34]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id KAA15663 for ; Tue, 4 Apr 1995 10:30:34 -0700 Received: from uni4nn.iaf.nl (root@uni4nn.iaf.nl [193.67.144.33]) by linux4nn.iaf.nl (8.6.9/8.6.9) with SMTP id TAA11831; Tue, 4 Apr 1995 19:39:33 +0200 Received: by uni4nn.iaf.nl with UUCP id AA13302 (5.67b/IDA-1.5); Tue, 4 Apr 1995 19:30:05 +0100 Received: by iafnl.iaf.nl with UUCP id AA20639 (5.65c/IDA-1.4.4); Tue, 4 Apr 1995 19:19:59 +0200 Received: (from wilko@localhost) by yedi.iaf.nl (8.6.8/8.6.6) id VAA01885; Mon, 3 Apr 1995 21:05:08 +0200 From: Wilko Bulte Message-Id: <199504031905.VAA01885@yedi.iaf.nl> Subject: Re: large filesystems/multiple disks [RAID] To: rgrimes@gndrsh.aac.dev.com (Rodney W. Grimes) Date: Mon, 3 Apr 1995 21:05:08 +1596657 (MET DST) Cc: peter@bonkers.taronga.com, terry@cs.weber.edu, PVinci@ix.netcom.com, hackers@FreeBSD.org In-Reply-To: <199504021655.JAA01937@gndrsh.aac.dev.com> from "Rodney W. Grimes" at Apr 2, 95 09:55:58 am X-Mailer: ELM [version 2.4 PL22] Content-Type: text Content-Length: 846 Sender: hackers-owner@FreeBSD.org Precedence: bulk > RAID does have the negative effect of of having to write 20% more data, > thus cutting effective bandwidth by 20%. It is actually worse than > this in that all writes must write to at least 2 drives no matter how > small they are. The removes some of the benifits of stripping. And that is why some RAID systems use (battery backed up please ;-) RAM caches. This works quite nicely. > Rod Grimes rgrimes@gndrsh.aac.dev.com > Accurate Automation Company Custom computers for FreeBSD Wilko _ __________________________________________________________________________ | / o / / _ Wilko Bulte email: wilko@yedi.iaf.nl |/|/ / / /( (_) Private FreeBSD site - Arnhem - The Netherlands --------------------------------------------------------------------------------