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From Jens Alfke <j...@couchbase.com>
Subject Re: Replication considerations
Date Fri, 12 Jul 2013 18:47:20 GMT

On Jul 11, 2013, at 1:44 AM, Boaz Citrin <bcitrin@gmail.com> wrote:

> 1. Performance wise, is it better to run the replication on machine A or B?
> (i.e. the source should be the remote machine or the local).

Generally, push replication is more efficient, for a couple of reasons:
* It doesn’t leave a socket connection open watching for changes (nor does it poll)
* The current replication protocol can push revisions in bulk, but not pull them in bulk,
so pull replications end up sending more HTTP requests.

> 2. What is the toll on running the tasks on both machines?
> (still having unidirectional replication, only from A to B.

You mean A runs a push to B, and B runs a pull from A at the same time? I wouldn’t recommend
that. At the very least it’ll involve more overhead as both hosts try to write the same
revisions to B at roughly the same time, with inevitably a lot of collisions.

—Jens
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