IBM OS/390 User Manual

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Operator Monitor Spool Utilization

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Spool Full Condition - $S SPL upon warning (Output limits minimize this)

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An external message-based automation product can also delete, offload or
reroute spool files.

Just as it is important to test new levels of OS/390 in your environment before
using them in production, you should also test any JES2 exits or modifications
before using them in production.

Secondary JES2 subsystems, or “Poly-JES,” provide you with the ability to test
new releases of JES2, and isolate JES2 work from the primary or production
copy of JES2. Many installations find this convenient because it does not require
a separate OS/390 test system.

There are two basic configurations for poly-JES:

 1. Sharing the spool and checkpoint with the primary JES

 2. Dedicating a unique spool and checkpoint to the secondary JES

See “Poly-JES” in Chapter 1 of the 

JES2 Initialization and Tuning Guide for

detailed guidance. This section is only an addendum to that material. You must
use a different character for the CONDEF CONCHAR parameter than the one
used by the primary JES, or the secondary JES2 will not initialize.

The number of secondary JES2 subsystems that can be active is limited only by
the number of different CONCHAR characters (22).

The remaining part of this chapter shows detailed comparisons between POWER
and JES2 parameters and commands.

The following tables can help you transfer most of the parameters you have
specified for POWER to their equivalent JES2 parameters.

In general, most of the JES2 initialization parameters have default values so you
do not need to specify them. Many installations start with the sample deck in
samplib - SHASSAMP - and modify those parameters as necessary.

You should review each of the parameters you specify that is different from the
default value using the 

JES2 Init & Tuning Reference manual. Here is a short

table to show you what POWER parameters can be specified in JES2:

Chapter 10. POWER and JES2