Do you run your batch JOBs in the order they are submitted?
Are your service level goals based on arrival times? So why do you
let DFHSM recalls all run at the same priority? With EASY/EXIT, you could
write 8 or 10 lines of selection language like the example below and
assign a priority to each request. This will be even more important if you
are implementing the Common Recall Queue. With this new feature in z/OS
1.2, all of the recalls are queued in the coupling facility and DFHSM
running on any LPARs in the Sysplex can satisfy the request. This should improve
recall response but it
also means a test LPAR could flood the queue with a lot of low priority
work that could affect production.
The following example shows just how easy it is to assign a priority to DFSHM
recalls
I*****************************************************************
*
*
* SAMPLE RULE TO SET PRIORITY FOR VARIOUS TYPES OF HSM RECALLS *
* THE DEFAULT PRIORITY IS 50
*
*****************************************************************
DEFRULE RCALPRTY
IF &ENV NE ARCRPEXT THEN CONTINUE AT NEXTRULE
/*********************************************/
/* PRODUCTION RECALLS HAVE A HIGH PRIORITY */
/*********************************************/
IF &QUAL2 = PROD*
&ENVS = RECALL
THEN SET &PRIORITY = 75
/**********************************************/
/* LOW PRIORITY FOR DAYTIME TAPE RECALLS
*/
/**********************************************/
IF &ENVS = RECALL
&DATA_SOURCE = TAPE
&CURTIME GT 09:00:00
&CURTIME LT 17:00:00
&CURDAY NE (SATURDAY,SUNDAY)
THEN SET &PRIORITY = 40
You could also set the priority based on the DFHSM HOSTID so recalls from
the test LPAR could not delay new requests from production.
This is just one example of the many functions of EASY/EXIT. You could
prevent the migration (or deletion) of critical data sets. Keep small data
sets on ML1 longer or send large data sets directly to ML2.
You could have fewer management classes because migration and deletion actions
can be modified by EASY/EXIT.
EASY/EXIT can also replace SMF exits like IEFUJI, IEJUJV and ABARS exits
as well. A simple console command is required to refresh the selection
language and there is a trace faclity to make testing easier. Sure, you can
code up one of these exits in Basic Assembler Language (BAL) but who has the
time or the skills required to make changes, test and debug assembler language
exits. I suspect there are lots of things you could do to add functionality
to z/OS, DFHSM and ABARS but have not because of the effort required to code,
test, and maintain system exits.
To find out how
more information and a complete list of exits supported, contact DTS Software
at 770 -922-2444 or info@DTSsoftware.com