Serving systems and distributed data

The serving system is the DBMS system that runs the remotely bound package.

Introductory concepts

If you are executing a package on a remote DBMS, then improving performance on the server depends on the nature of the server. If the remote DBMS on which the package executes is another Db2 subsystem, then you can use EXPLAIN information to investigate access path considerations.

Considerations that could affect performance on a remote Db2 server are:
  • The maximum number of database access threads that the server allows to be allocated concurrently. (The MAXDBAT subsystem parameter value.) A request can be queued while waiting for an available thread. Making sure that requesters commit frequently can let threads be used by other requesters.
  • The Workload Manager priority of database access threads on the remote system. A low priority could impede your application's distributed performance.
  • You can manage IDs through Db2 to avoid RACF® calls at the server

When Db2 is the server, it is a good idea to activate accounting trace class 7. This provides accounting information at the package level, which can be very useful in determining performance problems.