Path: utzoo!attcan!uunet!vsi!friedl
From: friedl@vsi.UUCP (Stephen J. Friedl)
Newsgroups: comp.unix.wizards
Subject: Re: Vax 11/780 performance vs Sun 4/280 performance
Summary: Micropolis
Keywords: readahead, striping, file mapping
Message-ID: <722@vsi.UUCP>
Date: 18 Jun 88 19:32:40 GMT
References: <22957@bu-cs.BU.EDU> <14968@brl-adm.ARPA> <601@modular.UUCP> <6963@cit-vax.Caltech.Edu>
Organization: V-Systems, Inc. -- Santa Ana, CA
Lines: 19

In article <6963@cit-vax.Caltech.Edu>, mangler@cit-vax.Caltech.Edu (Don Speck) writes:
>
> But they [parallel-head disks, I think] can be simulated with
> ordinary disks by striping across multiple controllers, *if* the
> disks rotate as one.  Does anyone know of a cost-effective disk
> that can phase-lock its spindle motor to that of a second disk,
> or perhaps with the AC line?

I think Micropolis has done this with a handful of their 700MB drives.
They put nine drives into a rack, use a special synchronizing controller,
and give you striped drives.  The ninth drive was for parity, and if
a drive failed, you could pull out the bad one and drop in the new
one: the controller would reconstruct the parity drive.  Sorry, I don't
have a reference...
-- 
Steve Friedl    V-Systems, Inc. (714) 545-6442      3B2-kind-of-guy
friedl@vsi.com     {backbones}!vsi.com!friedl    attmail!vsi!friedl

Nancy Reagan on the Mac-II architecture: "Just say Nu"