From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <5a727eb1d46489c965dcb7bfbcfc74eb@quanstro.net>
From: erik quanstrom <quanstro@quanstro.net>
Date: Thu, 15 Nov 2007 20:11:42 -0500
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Venti config for booting from fs(3)
In-Reply-To: <38CEF120-B324-41A1-8EB1-781E01CFC57A@gmail.com>
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since modern disks can read a whole track at once, there's no "reload"
time.  it would only make sense to interleave you have more than 1 i/o
process (venti seems to have a few) and you're either running faster
than the disk bandwidth.  the disk bandwidth could be as high as 60MB/s
for sequential reads and as low as 1MB/s for small reads with many seeks.

if most of venti's io is via the read ahead process, i think there would
be very limited benefit by interleaving i/o.  and you would need four
disks.  if you use two disks partitioned in =C2=BD, you will insure that =
every
write will generate a huge seek.

- erik