From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <e5f07d0c54afbaf136a997c63daf7145@plan9.ucalgary.ca>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] devfs
Date: Mon, 22 Nov 2004 21:30:01 -0700
From: andrey mirtchovski <mirtchov@cpsc.ucalgary.ca>
In-Reply-To: <20041123040223.GV44345@cassie.foobarbaz.net>
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>>>From reading the code, it looks like mirrors in devfs
> are read preferring the first drive in the mirror, and
> only reading from the second drive if there's a
> failure. Is this correct, and if so, is anyone working
> on round-robin reading to improve read performance?
> 

i believe that is true. 

would reading every other block from the second one improve
performance?  seems to me it would have the opposite effect, causing
many more seeks than normal (i.e.  there's no hd cache optimization
for 'read every odd/even block from the platter').

i see one clear benefit though, and that is if you have two or more
bulk readers and serve each one from a separate disk.

i'd like to hear other's opinions on this one :)

andrey