Wout Mertens <[EMAIL PROTECTED]> wrote:
> >>>> WOFS lives on a Write once medium, WOFS itself is not write once.
>
> Oops, now that I read your thesis, I see. So you can treat a WORM
> like a normal disk. Cool :)
Thank you ;-)
> How come it never got traction? There was a time in the 90s when it
> would have been great to have a stable writeable filesystem on cheap
> CD-ROMs. In fact, with dual layer DVDs right now, it still would have
> its uses. BTW, finding WOFS on Google is not the easiest thing :-(
I have no idea why nobody was interested. I did talk about it many
times in the 90s. Maybe the absence of web servers at that time
was the reason that the right people did miss the concept.
> While reading your thesis, I kept thinking that it should be possible
> for ZFS to be implemented on top of a WORM as well.
As it seems that ZFS is similar to WOFS in several places you may be right.
> Most of the hard bits are already done, checksums and copy-on-write.
> The only issue would be the root blocks that can't be overwritten,
> but that can be fixed like in your thesis, by growing an array from
> one side of the disk and putting all the data on the other side.
Correct.
> BTW, I would have put the generation nodes at the beginning of the
> disk and the data at the end, because then you can read the whole
> array in one big sequential gulp.
The gnodes grow backwards, but they are read in forwards.
> > Possible implementations are discussed in my master thesis:
>
> But it doesn't mention this solution ;-)
>
> Anyway, we might be straying a bit too far from the topic.
Well, I did not say it mentions _all_ posible solutions ;-)
Jörg
--
EMail:[EMAIL PROTECTED] (home) Jörg Schilling D-13353 Berlin
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[EMAIL PROTECTED] (work) Blog: http://schily.blogspot.com/
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