"Tape Ready" message from DFSMSrmm

[JimStout]

I'm looking for a way to have RMM issue a Tape Ready message for Specific (non-scratch) volumes at mount time. There are user mods available for CA1 but I'm having trouble locating a similar feature with RMM.

[JimStout]

I probably should have mentioned the reason for wanting to do this. I'm trying to measure Tape Mount Delay to understand its impact on Batch run time.

[enrico-sorichetti]

IIRC tape mount delays were/should-be available using some RMF report

[JimStout]

Yeah I thought so too. I was hoping that I could get it using VMA but it takes in SMF 14s, 15s and 21s. This will give Allocation Delay (not enough UCBs) but doesn't provide tape mount delay. If you know of something else that does, I would be very appreciative. Perhaps something in SMF30?

[enrico-sorichetti]

RMF III reports delays
a quick and dirty cut anf paste from the manual

You can use the Monitor III Utility to customize the DELAY report. In addition to the delays shown above you can use the Utility to have the following delay percentages shown.

Table 2. Additional Fields in the DELAY Report
Field Heading Meaning
% Delayed for
JES delay percentage
HSM delay percentage
XCF delay percentage
Operator mount delay percentage
Operator message delay percentage
Operator quiesce delay percentage
WLM resource group capping delay percentage

[steve-myers]

I did a project of this nature back in the 1980s. It was never updated to MVS/XA or more recent releases and the code has long since disappeared. In any event, what I think you want is rather indeterminate, so I'm not sure you'll get anything useful.

Just to give you an idea of the problem, JCL like this is all too common.

// EXEC PGM=SORT
//SORTIN DD – An existing tape data set -
//SORTOUT DD DISP=NEW,UNIT=TAPE,...

You'll see messages like this -

10:00:00.00 MOUNT vvvvvv ON iiii
10:00:00.00 MOUNT scrtch ON oooo
10:00:30.00 iiii READY

The presumptive time for the iiii READY message was typical of the robots of the era. In any event, while it's perfectly accurate and meaningful in that context, let's look at the output tape. Sort just needs SORTIN to start. Sort won't touch SORTOUT until it has read all of SORTIN. This is why you often see

//SORTOUT DD DISP=NEW,UNIT=AFF=SORTIN,...

The SORTOUT tape may be physically mounted while sort is reading through the SORTIN tape, but there will not be any indication of this in SYSLOG. Of course, sooner or later sort will finish with SORTIN. Then you'll see the messages for device oooo. Now what's the delay here? In practice, 0, because OPEN does not have to wait for the operator, or a robot, to mount the tape. But how do you measure it?

Like you I had hoped to use SYSLOG, but it was incomplete. I do not know if CA1 had come up with a mod for a dev xxxx READY message like you talk about, but I certainly didn't have it, but it wouldn't be seen until the data set was opened, which was too late much of the time. What I ultimately did was monitor the real UCBs.

[JimStout]

Steve (and others), thank you for your replies. Yes, CA1 has a usermod for the U01UX0A exit that allows a "Tape Ready" WTO to be issued at mount time. If you would like a copy, let me know. I was really hoping for something similar for RMM environments!