On 09/02/2009, at 1:08 AM, Damien Katz wrote:
Nope, each individual read operation gets a snapshot of the
database. When you are replicating, there is one read operation for
every document that must be sent. Each read request gives you a new
MVCC database.
This prompts the question - why not?
It seems to me that the consistency characteristics of replication
could be improved if a) MVCC boundaries were created by update
operations and b) a given replication was bounded by the latest MVCC
state available when the replication was started i.e. replication
cannot race with updates. I presume replication cannot use a single
MVCC state because it needs to see revisions? If revisions are visible
within a state, then my question would be why replication doesn't use
a single MVCC state.
Antony Blakey
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CTO, Linkuistics Pty Ltd
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