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From: Dirkjan Ochtman <dirkjan@ochtman.nl>
Date: Fri, 5 Mar 2010 17:08:05 +0100
Message-ID: <ea2499da1003050808s2cd953cfn3b226ef1ee501330@mail.gmail.com>
Subject: Preserving seq order through replication
To: dev@couchdb.apache.org
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Hi there,

I recently started using continuous replication to propagate a
document stream from a producing server to a consuming server. The
producing server is fed by a single process that puts messages in, and
on the consuming server we have a process reading the continuous
changes feed to get messages back out and process them. We migrated to
this from having a single server that both processes talked to because
the connection between the servers isn't always reliable,
unfortunately.

This worked rather well for about 50 hours, but now it turns out that
in some cases the continuous replication doesn't always preserve the
ordering of the sequence. That is, the insertion order, which is
consistent on the producing server (as expected, as there's a single
feeding process doing a single update per document) doesn't match the
order in the continuous feed of changes on the consuming server.

This is kind of a WTF. Could it be fixed?

Cheers,

Dirkjan