Episode 8 "Queue Me Up"

Here are the show notes for Episode 8 "Queue Me Up". The show is called "Queue Me Up" because:

• Marna talks about moving up to higher z/OS releases...or releases "in the queue".
• Martin talks about the Coupling Facility list structures...or "queues".

We had some follow up:

• IBM Doc Buddy - available for iOS and Android.
• The latest iOS level is currently 1.1.1. The latest Android level is currently 1.1.2. Still keep an eye out for updates, as they are coming out periodically and delivering requested functions.
• Continuous Delivery Follow-up
• October 4, 2016: A DB2 12 recent announcement includes their Continuous Delivery message, with new functions via the service stream: IBM DB2 12 for z/OS expands the value offered to your business by IBM's industry-leading mainframe data server

Mainframe

Our "Mainframe" topic was a discussion on z/OS upgrade timing considerations.

z/OS R13 is now out of service since end of September 2016, five years of regular service support since GA. There are three consecutive releases of coexistence (with releases planned on coming out every two years).

This "discrepancy" between five years of service and and six years (three times two) of coexistence has been quite interesting and deserves some thought. Marna talks about some considerations, and it might be that the "n-2" model should be reconsidered to be a "n-1" model for some customers.

Performance

Our "Performance" topic was an extension of this blog post of Martin's: Right On Queue.

Martin talks about Coupling Facility list structures, and how they are different from lock and cache structures. He also covers some considerations and causes for how they might get filled up. (Think of the analogy of a pipe getting blocked as one case.)

Sizing is important and he uses SMF 74-4 and RMF Monitor III. A good rule of thumb is that your structure's maximum size should be in the range of 50% to 100% of the current size. More than double puts you at risk of having a list structure full of control blocks and little data. You also need to monitor how much of the current size is actually in use.

Topics

In our "Topics" section we discussed a travel app called Waze. It's a crowd-sourcing app you can use to get real-time travel estimates and routes. It also alerts you about such items as accidents, debris, police cars, etc, which other users have reported. This app is particularly useful even if you have to put up with a very small amount of advertising.

Contacting Us

You can reach Marna on Twitter as mwalle and by email.

You can reach Martin on Twitter as martinpacker and by email and blogs at blog.