From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Pittman <daniel@rimspace.net>
Subject: Re: Raid on USB2 ?
Date: Sat, 18 Feb 2006 12:11:28 +1100
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Ken Walker <ken.walker@manchester.ac.uk> writes:

> Anybody tried a Raid1 or Raid5 on USB2.
>
> If so did it crawl or was it usable ?

Yes, I used this for two by two drive RAID-1 arrays.

It was usable, but not pleasantly.  The machine became very I/O bound,
with human scale delays introduced into previously "instant" processes
such as opening an IMAP mailbox, scanning a directory listing, etc.

I wouldn't advise more than two or three drives per USB controller, and
would expect poor performance even then.

    Daniel