Replication Server provides four different serialization methods for specifying the level of parallelization. The serialization method you choose depends on the amount of contention you expect between parallel threads and your replication environment. Each serialization method defines how much of a transaction can start before it must wait for the previous transaction to commit.
Use the dsi_partitioning_rule parameter to reduce the probability of contention without reducing the degree of parallelism assigned by the serialization method. See “Partitioning rules: reducing contention and increasing parallelism”.
The serialization methods are:
no_wait
wait_for_start
wait_for_commit
wait_after_commit
Use the alter connection command with the dsi_serialization_method parameter to select the serialization method for a database connection. For example, enter the following command to select the wait_for_commit serialization method for the connection to the pubs2 database on the SYDNEY_DS data server:
alter connection to SYDNEY_DS.pubs2 set dsi_serialization_method to 'wait_for_commit'
A transaction contains three parts:
The beginning
The body of the transaction, consisting of operations such as insert, update, or delete
The end of the transaction, consisting or a commit or a rollback
While providing commit consistency, the serialization method defines whether the beginning of the transaction waits for the previous transaction to become ready to commit or if the beginning of the transaction can be processed earlier.
