DFSMShsm can have up to 15 volume backup tasks running concurrently
in each host. The MAXBACKUPTASKS parameter of the SETSYS command controls
the number of concurrent volume backup tasks that will run. To decide
how many concurrent volume backup tasks DFSMShsm should run, consider
how many tape units are available if you use tape backup volumes or
how many backup DASD units are available. If you are using the duplex
tape option for backups, you will need two tape units for every backup
task. Also, consider the system work load when volume backup is running.
The default for this parameter is 2.
Note: In a multiple
DFSMShsm-host environment with concurrent multitasking, it is beneficial
to run all tasks on a single host. For example, having eight tasks
running automatic backup from one host gives you better performance
than splitting the tasks and running four on one host and four on
another host.
In the example system, the maximum backup tasks are specified as:
SETSYS MAXBACKUPTASKS(3)