I was reading about XA Transactions in the documentation
http://dev.mysql.com/doc/refman/5.0/en/xa.html
and near the end it says "The process for executing a global transaction
uses two-phase commit (2PC). This takes place after the actions performed
by the branches of the global transactions have been executed."
Does this mean that two-phase commit incurs 3 round trips? One round trip
for the branches of the global transaction to be sent, executed at their
local site, and a response. A second round trip for the prepare phase
message and response. A third round trip for the commit phase message and
response.
