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From Filipe David Manana <fdman...@gmail.com>
Subject Re: _replicator DB
Date Thu, 20 May 2010 15:17:30 GMT
One question Adam:

On Wed, May 19, 2010 at 8:35 PM, Adam Kocoloski <kocolosk@apache.org> wrote:

>
> > 3) Is the checkpoint ID generation algorithm backwards-compatible?  Or
> will users who upgrade restart all replications from scratch?
> >
>

To make it backward compatible, it means that independenly of replication
document IDs, the _local documents would be the the same as before - that
md5 of term_to_binary over a term composed of replication properties
(source, target, continuous, etc).

This way 2 replications document that differ only on their ID, would share
the same replication log _local docs. If both are updating them, we have
racing conditions, so one of the replication gen_servers will fail.

Remembering now this was the main reason I opted to assign IDs like
"_local/repDocId" to the replication logs, breaking backward compatibility.

Some suggestion?

cheers


-- 
Filipe David Manana,
fdmanana@gmail.com

"Reasonable men adapt themselves to the world.
Unreasonable men adapt the world to themselves.
That's why all progress depends on unreasonable men."

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