On 09/02/2009, at 10:09 PM, Antony Blakey wrote:
On 09/02/2009, at 9:33 PM, Antony Blakey wrote:
2. Record commit boundaries, possibly by recording a transaction-
seq with each document rev. I'm aware that this *is* about reifying
underlying transactions, but at least the reification is implicit.
Actually, that could form the first part of the new compound revs
Assuming the replication processes doesn't interleave documents from
different MVCC commits, I'm now thinking that all that is needed is
for each rev to include a MVCC commit # (== transaction id); commit
#'s would be allocated at the start of an MVCC transaction (because
they would be needed within the commit), and hence would not be a
strict ordering. You can then detect MVCC commit boundaries by
detecting when the commit # changes. No change required to the source
replicator, and target replication could take advantage of that at
some future stage.
This would allow for consistent replication of transactions, if they
were provided, with replication possible at a MVCC commit granularity
i.e. no problem with huge replications.
Antony Blakey
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