Loading %%GLOBAL Members to Cache

%%GLOBAL members can be placed in cache memory from where they can be accessed as needed. If the members are placed in cache, the JCL accesses the contents from the cache, instead of accessing the members themselves.

This can be very advantageous if many jobs access %%GLOBAL members, because each access of the member increases I/O and processing overhead. Only those %%GLOBAL members that are specifically requested are loaded to cache.

Requests are generally made by listing the desired %%GLOBAL members in a special cache list member in the DAGLOBAL library. This cache list member (default name: CACHLST) is pointed to by parameter AECACHL in member CTMPARM in the IOA PARM library.

Use the following format to list members in the cache list member:

where memname is the name of the %%GLOBAL member pointed to by DD statement DAGLOBAL.

The cache list member can optionally contain the following control statement as its first non-comment statement:

This control statement affects AutoEdit processing only if an AutoEdit variable has not been resolved by searching the %%GLOBAL members identified in the job. The statement instructs Control‑M to continue the variable resolution process by checking all members loaded into cache. Members in cache are searched in the same sequence they are listed in the cache list member.

%%GLOBAL members are loaded to cache:

• In the Control-M monitor's address space, at the time of Control-M startup.
• In the online address space, when the user performs AutoEdit simulations (options 2.%, 3.%, or 6.M2 ), or enters a JCL edit session (2.J or 3.J).

  At the end of the option processing, the AutoEdit cache is deleted.

• In the batch AutoEdit simulation job.

The following commands can be used between Control-M startups, and affect only the Control-M monitor's cache processing.

To reload %%GLOBAL members to cache, specify the reload command in either of the following formats:

Each of these formats deletes the current %%GLOBAL members from cache, and then (re)loads to cache the %%GLOBAL members listed in the cache list member.

If the command is specified without a member name, the name of the cache list member that was last loaded is used. This format is especially useful if there are changes to the list of %%GLOBAL members in the cache list member and/or changes to the contents of the currently loaded %%GLOBAL members.

If the command is specified with a member name, the member name must identify a cache list member in DAGLOBAL (other than the currently active cache list member).

To stop using AutoEdit cache, issue the following command: