Displaying spool information enables you to monitor JES2 spooling and determine the action to take to control the spool environment. You can use the $D SPOOL command to display the status and utilization of spool volumes. Use the $D JOBQ,SPOOL=(%>NN) to display all the jobs in the configuration that are using a specified amount of spool space.

The SPOOLDEF initialization statement sets the maximum number of spool volumes (1-253) allowed in the MAS configuration. The number you specify is automatically rounded up to a multiple of 32. For example, if you specify SPOOLNUM=33, a maximum of 64 spool volumes is allowed in the MAS configuration. Use the $T SPOOLDEF command to dynamically change some of the JES2 spooling environment characteristics.

You can add (and, optionally, format) a new spool volume dynamically or when performing a cold start by issuing the $S SPOOL command. Additionally, you can use the $S SPOOL command to reactivate a previously inactive volume. Jobs allocate space on the volume only after it has completed start processing. While the volume is starting, other processing within the system continues normally.

You may also drain and delete spool volumes dynamically using the $P SPOOL command as well as halt entire spool volumes using the $Z SPOOL command. Any spooled messages or JESNEWS data sets residing on the volume to be halted or drained are moved to an active spool volume.