[Date Prev][Date Next] [Chronological] [Thread] [Top]

replicate internal operations (was: (ITS#6915) memberof+accesslog duplicate reqStart)

Taking this to -devel for clarification.

hyc@symas.com wrote:
The original design for memberOf was for the internal modifications to not be
replicated. Instead, any replicas that wanted to maintain member information
was expected to run an identical memberOf overlay configuration.


In general it's incorrect to replicate internal operations. The fanout from
replicating every internal operation would be too large and the information
content of what is being replicated is essentially nil. When the servers are
configured identically they will maintain identical data by virtue of the
overlays on each node performing the same internal operations in response to a
given sequence of user operations.

While I agree here I think "internal operations" has to be defined a little bit more clear: What about extended operations which may result in several write operations? Extended operations are not written to the accesslog-DB and are not replicated.

Ciao, Michael.