What you should know about the z/VM *MONITOR record reader device driver

The data that is collected by *MONITOR depends on the setup of the monitor stream service.

The z/VM *MONITOR record reader device driver only reads data from the monitor DCSS; it does not control the system service.

z/VM supports only one monitor DCSS. All monitoring software that requires monitor records from z/VM uses the same DCSS to read *MONITOR data. Usually, a DCSS called "MONDCSS" is already defined and used by existing monitoring software.

If a monitor DCSS is already defined, you must use it. To find out whether a monitor DCSS exists, issue the following CP command from a z/VM guest virtual machine with privilege class E:
q monitor
The command output also shows the name of the DCSS.

Device node

SUSE Linux Enterprise Server 12 SP4 creates a device node, /dev/monreader, that you can use to access the monitor DCSS.

Further information

  • See z/VM: Saved Segments Planning and Administration, SC24-6322 for general information about DCSSs.
  • See z/VM: Performance, SC24-6301 for information about creating a monitor DCSS.
  • See z/VM: CP Commands and Utilities Reference, SC24-6268 for information about the CP commands that are used in the context of DCSSs and for controlling the z/VM monitor system service.
  • For the layout of the monitor records, go to www.ibm.com/vm/pubs/ctlblk.html and click the link to the monitor record format for your z/VM version.