From mboxrd@z Thu Jan  1 00:00:00 1970
From: "John E. Barham" <jbarham@jbarham.com>
Subject: Re: [9fans] venti block score & type
To: 9fans@cse.psu.edu
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 <E1AUdlw-0000Ex-22@t40.swtch.com>
Date: Thu, 11 Dec 2003 20:05:10 -0800
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> > Similarly, that attempting to write a block whose score is already in
venti,
> > but with a different type, will fail?
>
> No.  A new index entry will be written for the new type.
>
> Types are really just to help a little in interpreting the
> data.  They're almost purely advisory.  (Almost, because
> the answer to your first question is yes.)  Since blocks are
> zero-truncated before storing, the zero-length block
> might reasonably be interpreted as a data block or as
> a pointer block of any depth.  Similarly, if I store a file
> whose contents are the SHA1 hash of a small file, that
> contents will be stored as data, but storing the small file
> itself would use the same block as a first-level pointer
> block.

So venti stores a list of types written for each score?  Thus reading a
block would require that the type be in that list, but writing a block would
add the type to the list if it was not already present?

    John