Improving distributed relational database performance through the network

Among them are the following ways:

• Line speed
• Pacing
• Frame size
• RU sizing
• Connection type (nonswitched versus switched)
  Note: Unprotected conversations are used for DRDA connections under one of the following circumstances:

  • When the connection is performed from a program using remote unit of work (RUW) connection management
  • If the program that is making the connection is not running under commitment control
  • If the database to which the connection is made does not support two-phase commit for the protocol that is being used

  If the characteristics of the data are such that the transaction only affects one database management system, establishing the connection from a program using RUW connection management or from a program running without commitment control can avoid the overhead associated with two-phase commit flows.

  Additionally, when conversations are kept active with DDMCNV(*KEEP) and those conversations are protected conversations, two-phase commit flows are sent regardless of whether the conversation was used for DRDA or DDM processing during the unit of work. Therefore, when you run with DDMCNV(*KEEP), it is better to run with unprotected conversations if possible. If running with protected conversations, you should run with DDMCNV(*DROP) and use the RELEASE statement to end the connection and the conversation at the next commit when the conversation will not be used in future units of work.