From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <11aaa855361fd5ac7e637be3d37d3116@hamnavoe.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] venti ports and productization
From: Richard Miller <miller@hamnavoe.demon.co.uk>
In-Reply-To: <E1ABymF-0000VR-7q@t40.swtch.com>
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Date: Wed, 22 Oct 2003 15:57:15 +0100
Topicbox-Message-UUID: 775cb812-eacc-11e9-9e20-41e7f4b1d025

> We have had some problems
> with the big Venti server, but my understanding is that
> all of the problems appeared to be disk corruption rather
> than software error.

The software could do a bit better in recovering from hardware errors.
If a bad sector makes a venti block unreadable, rdarena and wrarena
could use the redundant information in the arena trailer to skip the
bad block and continue, but they just give up.  Worse, if checkarenas
(with -f) fails to read a block, instead of using the trailer information
to skip the block, it tries to correct the mismatch between block label
and trailer by copying garbage into the trailer entry from the buffer
it just failed to read into.  Oops.

-- Richard