Evaluating zIIP Usage

In order to evaluate server zIIP processing in a session, you can query three Dialogue Manager variables that accumulate statistics about CPU processing:

• &FOCCPU accumulates the time spent on a Central Processor. This is an existing variable that precedes zIIP enablement.
• &FOCZIIPCPU accumulates the time actually spent on the zIIP processor (in SRB mode). This is the normalized CPU value using the same scale as &FOCCPU.
• &FOCZIIPONCP accumulates the time that processing could have been offloaded to the zIIP processor but was diverted to the Central Processor by the system.

  Note:

  • &FOCCPU includes the value of &FOCZIIPONCP.
  • The sum of &FOCZIIPCPU and &FOCCPU represents the total CPU utilized by the server agent.
  • If you set ZIIP=OFF, the zIIP variables do not accumulate further but are not reset to zero. If you later set ZIIP=ON, they resume accumulating statistics.

The RM (Resource Manager) that monitors server usage also captures zIIP statistics.