Re: [9fans] Ideas for gc on venti

[Enrico Weigelt <weigelt@metux.de>]

* Russ Cox <rsc@swtch.com> wrote:

Hi,


> The greatest strength of venti, and also of
> the worm file system, is that once data is written,
> those disk blocks are never changed again.

Yep, but my scenario is not completely worm.
Some data might be removed/unused. Even it might not be absolutely
necessary, it would be nice to reclaim space.

> Why not just use an ordinary file system?
> What benefit are you deriving from using venti
> that is making all this rewriting worthwhile?

Venti makes lots of things easier, eg. it avoids duplicated data.
For example, if some users upload already existing media, I've
just got one more db record, but no duplicate data. Doing this
on fs basis would require more logic on application side.

Another, very important, point is that I'm creating an cloud venti,
which synchronizes with its peers on-demand and distributes the
data over the cloud. So I don't need additional logic for
clustering the application / it's data spaces.
(I'll also use the venticloud for several other things, eg. for
building an distributed fs or something like S3 on it).


cu
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 Enrico Weigelt, metux IT service -- http://www.metux.de/

 cellphone: +49 174 7066481   email: info@metux.de   skype: nekrad666
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