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From Filipe David Manana <>
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 <> 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?


Filipe David Manana,

"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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