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Mainframe, Performance, Topics Podcast

Mainframe, Performance, Topics Podcast

By Marna Walle

Martin Packer (Principal z Systems Investigator) and Marna Walle (z/OS Development) are two IBMers talking about whatever z/OS topics come to mind. Often guest experts weigh in on current technologies. This podcast will give you timely, interesting, and entertaining z/OS topics. Each episode comprises a “Mainframe” item, a “Performance” item, and “Topics” which is anything Martin or Marna care to talk about, which might or might not be related to their jobs. So it goes…
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Episode 13 "We'll Always Have Paris"

Mainframe, Performance, Topics PodcastMar 21, 2020

Episode 33 "These Boots Were Made"

Episode 33 "These Boots Were Made"

Episode 33 "These Boots Were Made"

What’s New

Mainframe -

  • Requires: z/OS V2.5 with PTFs, IBM z16 with microcode. Has both driving and target system requirements, use IBM.Function.ValidatedBoot FIXCAT.
  • Front end: Siging the in-scope artifacts (NUCLEUS, LPA, IPL Text, and SA Dump Text), z16 is not required here although z/OS V2.5 and PTFs are.
  • Back end: Verification of those signed in-scope artifacts. z16 with correct microcode level is required here (with z/OS V2.5 and PTFs).
  • Security set up work is required.

Performance - Open Data Sets, Part 2

  • Follow on, from Part 1 which was physical open and close of data sets as seen by z/OS.
  • This is about Db2 with the notion of logically Open and Closed data sets.
  • Its main role is to manage inter-Db2 read/write interest, for Datasharing efficiency purposes.
  • Two Db2 subsystem parameters have traditionally been used to control pseudoclose: PCLOSET and PCLOSEN. PCLOSEN is gone in V12 with APAR PH28280, as part of a DSNZPARM simplification effort. So PCLOSET would need adjusting down to whatever mimics PCLOSEN - in anticipation of this APAR or V13.

Topics - Messing With Digital Electronics

  • Martin explores his experiences with input devices (Stream Decks, Quick Keys, ...)
  • Martin has even built his own input devices: having an RFID card kick off automation, rotary encoders, USB Human Interface Device.

On the blog

So It Goes

Jul 05, 202340:04
Episode 32 "Scott Free"

Episode 32 "Scott Free"

Episode 32 "Scott Free" What’s New Mainframe - SMFLIMxx Parmlib Member
  • IEFUSI exit replacement with a parmlib member, related to storage and limits that can be specified.
  • Functions are delivered as continuous delivery, such as the SAF check filter, and number of shared pages used.
  • In z/OS 3.1: Dedicated Real Memory Pools to assign memory to a specific application, like zCX, in all frame sizes.
Performance - Open Data Sets, Part 1
  • Looking at many open data sets (100s of thousands) for middleware.
  • ALLOCxx's SWBSTORAGE has to specify ATB to put control blocks above the bar. Applications need to exploit the service.
  • Monitoring virtual storage is key here, and remains important. The number of volumes needed affects how much memory is needed, so there is no one answer.
Topics - Evolution of a Graph
  • Martin explores the large improvements he's made with his custom graphing programs.
  • Start with naive rows and columns, with rigid labels.
  • Then, generating the titles with REXX. Then, using REXX to drive GDDM directly. Then, use REXX to generate many more data point and plotting them directly. Then, have REXX generate the series names.
  • Martin encourages all to evolve their graphs, to tell the story better, and run more efficiently.
Customer Requirement
  • ZOSI-2195 "Extended GDG causes space issues", has been satisfied. IGGCATxx's GDGLIMITMAX with OA62222 on V2.3.
On the blog
  • Marna's NEW blog location is here
  • Martin has quite a few new blog articles here
So It Goes
Apr 21, 202341:14
Episode 31 "Take it to the Macs"

Episode 31 "Take it to the Macs"

Episode 31 "Take it to the Macs" show notes.

This episode is about our After Show. (What is that?) Long show notes can be found here.

What’s New Mainframe - z/OS Management Services Catalogs: Importance of z/OSMF Workflows
  • z/OS Management Services Catalog, zMSC, allows you to customize a z/OSMF Workflow for your enterprise, and publish it in a catalog for others to "click and use".
  • There are 7 initial sample Services that IBM provides, or you can provide your own with a starting Workflow.
  • zMSC Services are based on z/OSMF Workflows. You can see why the discussion on knowing z/OSMF Workflows is important.
Performance - System Recovery Boost (SRB) Early Experiences
  • System Recovery Boost provides boosts of two kinds: speed and zIIP.
  • There are different capabilities of SRB, based on which HW server you are running (z15 or z16):Shutdown - which allows you to have 30 minutes worth of boosting during shutdown. This function must be requested to be used each time.
    IPL - which allows you to have 60 minutes worth of boosting during IPL. This function, provided by default, is on.
    Recovery Process Boost, provided on IBM z15. Extends to structure or connectivity recovery, for instance.
    Newer additional functions for Recovery Process Boost, specifically on IBM z16, for stopping and starting certain middleware.
  • Martin has several early field experience, which he has summarised in four blog posts.
Topics - Stickiness
  • This topics explores what makes some technologies sticky, and some not.
  • Martin and Marna discuss some of the attributes are important for continuing to be used, and what makes a function fall away over time.Value
    Usability and immediacy
    Setup complexity
On the blog
  • Marna's blog is here
  • Martin has quite a few new blog articles here
So It Goes
Jul 11, 202244:48
Episode 30 "Choices Choices"

Episode 30 "Choices Choices"

Short show notes - long show notes here

We have a special guest joining us for the performance topic, Scott Ballentine.

What’s New
  • New news for CustomPac removal date, which has been extended past January 2022. The reason was to accommodate the desired Data Set Merge capability in z/OSMF which customers needed. For the new withdrawl date, it is planned to be announced in 2Q2022.

    Mainframe - Only in V2.5
  • This topic was looking at some new functions that are only in z/OS V2.5.

    • Data Set File System, planned to be available in 1Q 2022.
    • Dynamic Change Master Catalog
    • RACF data base encryption has a statement of direction.
    • Increase z/OS Memory limit above 4TB to 16TB.
    • More Concurrently ”Open” VSAM Linear Datasets. Db2 exploits with Apar PH09189, and APAR PH33238 is suggested.
    • ISPF Updates to ISPF in support of PDSE V2 member generations, and SUBMIT command to add an optional parameter SUBSYS.
    • Access Method Services - IDCAMS - DELETE MASK has two new options TEST and EXCLUDE
    • z/OS Encryption Readiness Technology zERT
  • There’s a lot of other stuff rolled back to V2.4

    Performance - What's the Use? - with special guest Scott Ballentine
  • This discussion is a summary from a joint presentation on Usage Data and IFAUSAGE

  • The topic is motivational because customers can get a lot of value of out this usage data, and understand the provenance of IFAUSAGE data.
  • A macro vendors or anybody use can use to show which products are used and how. It can show names: Product Vendor, Name, ID, Version, Qualifier, Show numbers: Product TCB, Product SRB, FUNCTIONDATA
  • The data is ostensibly for SCRT, which is fed by SMF 70 and SMF 89
  • Scott talked about encoding via IFAUSAGE, appears in SMF 30 and 89-1
    • SMF 89-1: Software Levels query, Db2 / MQ subsystems query
    • SMF 30: Topology (e.g. CICS connecting to Db2 or MQ), Some numbers (Connections’ CPU)
    • Both SMF 30 and 89: FUNCTIONDATA
  • Examples were mentioned that might inspire developers to think about how they code IFAUSAGE
  • Hope is developers will delight customers by using IFAUSAGE right, and customers will take advantage in the way shown with reporting examples.

    Topics - Choices, Choices
  • This topics is about how to choose a language to use for which purpose. Different languages were discussed for different needs.

  • Use Case: Serving HTML?
  • Host consideration: Running on e.g. laptop?
  • Host consideration: Running on z/OS?
  • Overall lesson: Choose the language that respects the problem at hand.

    On the blog
  • Marna's blog is here

  • Martin has quite a few new blog articles here So It Goes
Mar 16, 202235:39
Episode 29 "Hello Trello"

Episode 29 "Hello Trello"

This episode is about how to be a better z/OS installation specialist, z/OS capture ratios, and a discussion on using Trello. We have a special guest joining us for the performance topic, Miroslava Barahona Rossi.  Long show notes are found here .

Mainframe - Being a Better Installation Specialist

  • "Better" here means lessons learned, not competing with people. "Installation Specialist" might just as well have used "System Programmer" or another term.
  • There's definitely a reason to be optimistic about being a person that does that Installation Specialist or System Programmer type of work:
  • There will always be a need for someone to know how systems are put together, how they are configured, how they are upgraded, and how they are to just get things to run.
  • Consider the new function adoption needs too. There are so many "new" functions that are just waiting to be used.
  • A really good installation specialist would take information they have and use it in different ways.
  • Knowing parmilb really well.
  • You can't be better by only doing things yourself, no one can know everything. You've got to work with others who are specialists in their own area.
  • Last but not least, learn how to teach yourself. Know where to find answers (and that doesn't mean asking people!). Learn how to try out something on a sandbox.

Performance - Capture Ratio

  • Our special guest is Miroslava Barahona Rossi, a technical expert who works with large Brasilian customers.
  • Capture Ratio - a ratio of workload CPU to system-level CPU as a percentage.
  • Commercial considerations when billing for uncaptured cycles. You might worry something is wrong if the capture ratio is low.
  • Reasonable value is usually 80 - 90. Seeing more like 85 - 95 these days. It has been improved because more of I/O-related CPU is captured.
  • Summary:
  • Don’t be upset if you get a capture ratio substantially lower than 100%. That's normal.
  • Understand your normal. Be aware of the relationship of your normal to everybody else’s. But, be careful when making that comparison as it is very workload dependent.
  • Understand your data and causes. See if you can find a way of improving it. Keep track of the capture ratio over the months and years.

Topics - Hello Trello

  • Trello is based on the Kanban idea.
  • Why are we talking about Trello?  We moved to it for high level podcast planning.  Template used for hatching new future episodes. We move cards around sometimes between episodes.
  • Marna uses it to organise daily work, with personal workload management and calendaring. But it is not a meetings calendar.
    Probably with Jira will be more useful than ever. We'll see.
  • Martin uses it for team engagements, with four lists: Potential, Active, Dormant, Completed. Engagement moves between lists as it progresses

Martin's blog
Marna's blog

So It Goes.

Apr 20, 202159:56
Episode 28 "The Preview That We Do Anew"

Episode 28 "The Preview That We Do Anew"

This episode is about several of the z/OS V2.5 new functions, which were recently announced, for both the Mainframe and Performance topics. Our Topics topic is on Martin's Open Source tool filterCSV.  Full long show notes are here.

We have a guest for Performance: Nick Matsakis, z/OS Development, IBM Poughkeepsie.

Many of the enhancements you'll see in the z/OS V2.5 Preview were provided on earlier z/OS releases via Continuous Delivery PTFs. The APARs are provided in the announce.

If you use FTPS for your IBM software electonic delivery, a change is taking place on April 30, 2021. We strongly recommend you use HTTPS instead, but if you still want to use FTPS see IBM software electronic delivery change - take notice!

Mainframe - Selected z/OS V2.5 enhancements
  • IBM will have z/OS installable with z/OSMF, in a portable software instance format! z/OS V2.4 will not be installable with z/OSMF, and z/OS V2.4 driving system requirements remain the same. z/OS V2.5 will be installable via z/OSMF, so that is a big driving system change.
  • Learn z/OSMF Software Management at this website.
  • Notification of availability of TCP/IP extended services
  • Workload Manager (WLM) batch initiator management takes into account availability of zIIP capacity
  • Change the Master Catalog without IPL
  • IDCAMS DELETE mask takes TEST and EXCLUDE.
  • IDCAMS REPRO moves I/O buffers above line.
  • New RMF Concept for CF data gathering
  • RMF has been restructured, but all the functions are still intact. z/OS V2.5 RMF is still a priced feature.
Performance - zCX enhancements
  • zCX is important for co-locating Linux on Z containers with z/OS.
  • Popular use cases can be found here and in the Redbook here. Another helpful source is Ready for the Cloud with IBM zCX.
  • zIIP eligibility enhancements
  • New enhancements include support 1 MB and 2 GB large pages (still fixed) for backing guests.
  • Guest memory is planned to be configured up to 1 TB
  • Another relief is in Disk space limits
  • Monitor and log zCX resource usage of the root disk, guest memory, swap disk, and data disks in the servers job log.
  • zCX resource shortage z/OS alerts to improve monitoring and automated operations.
  • SIMD (or Vector). SIMD is a performance feature, and can be used for analytics.
  • Nick's presentation (with Mike Fitzpatrick) is here.
Topics - filterCSV and tree manipulation
  • Mindmapping leads to trees. Thinking of z/OS: Sysplex -> System -> Db2 -> Connected CICS leads to trees.
  • Has very little automation of its own. But crucially you can mangle the CSV file outside of iThoughts, which is what filterCSV does.
    • filterCSV is a python open source program that manipulates iThoughts CSV files, colouring CICS regions according to naming conventions

So it goes.

Mar 02, 202149:40
Episode 27 "And Another Thing"

Episode 27 "And Another Thing"

Episode 27 "And Another Thing" show notes.  Long show note are here. Follow up
  • Additional System Recovery Boost enhancements:
    • Sysplex partitioning recovery: Boosts all surviving systems in the sysplex as they recover and takes on additional workload following the planned or unplanned removal of a system from the sysplex.
  • Two more portable software instances: Db2 and IMS added to Shopz on Aug 20, 2020, in addition to CICS (Dec 2019).

Martin was asked about which systems in a System Recovery Boost Speed Boost situation get their GCPs sped up to full speed.

Mainframe - Trying out Ansible for driving z/OSMF Workflows
  • Marna's been learning about Ansible and how it can drive z/OSMF work. So far with z/OSMF Workflows, from ansible-galaxy collection for ibm.ibmzoszosmf
  • Needed lots of assistance from two gracious Poughkeepsie system testers (massive thanks to Marcos Barbieri and Daniel Gisolfi !!)
  • Encountered two kinds of problems:
  • Security issues connecting the Linux environment to a large Poughkeepsie System Test z/OSMF environment
  • Workflow-related: duplicate instances when part of the playbook ran ok, and selecting an automated workflow.
Performance - So You Don't Think You're An Architect?
  • Brand new presentation for 2020, builds on the “who says what SMF is for?” slide in "How To Be A Better Performance Specialist"
  • Presentation talks about 3 layers
  • The Top Layer - Machines, Sysplexes And LPARs
  • The Middle Layer - Workloads And Middleware: Spikes, Restarts, Cloning, Topology, Software Levels
  • The Bottom Layer - Application Components: Db2 and MQ Accounting Trace, DDF topology, data sets
  • Fulfilling the definiton Of Architecture? Understand what's really going on and valuable to system architects
Topics - Notifications
  • They are unsolicited messages appearing on the device, generally interruptions whether wanted or not.
  • Examples of what is received and where/
  • How do you manage them to reduce their number.
  • An advanced topic is how you can generate your own
  • On iOS the Pushcut app: a webhook from eg IFTTT can cause a notification
  • On Android we have MacroDroid.
Customer requirements
  • Customer Requirement 138729 : z/OS Console message help support JES2 messages
    • IBM response: This RFE has been delivered via APAR PH24072 at end of June 2020. It's available on both V2R3 and V2R4. The JES2 message prefix such as $ can be setup in "Configure Message Help" dialog in z/OSMF Console UI.
On the blog

So it goes.

Nov 16, 202056:37
Episode 26 "Sounding Board"

Episode 26 "Sounding Board"

Here are the show notes for Episode 26 "Sounding Board". The show is called this because it relates to our Topics topic, and because we recorded the episode partly in the Pougkeepsie recording studio where Martin sounded zen, and partly at home.

What’s New
    • PTF Numbers are UI68359 for 2.3 and UI68360 for 2.4
  • APAR OA56774 (since 2.2) Provides new function to prevent a runaway sysplex application from monopolizing a disproportionate share of CF resources
    • Not based on CF CPU consumption. Is based on deteriorating service times to other structures - which you could measure with SMF 74-4 Coupling Facility Activity data.
Mainframe - z15 FIXCATs
  • IBM.Device.Server.z15-8561.RequiredService: Absolute minimum needed to run on a z15. Usually intent is to keep these PTFs to a minimum - and keep the number of PTFs relatively constant.  <>
  • IBM.Device.Server.z15-8561.Exploitation: Needed for optional functions, and you can decide when you want to use them. This PTF list could grow - if we add new functions
  • IBM.Device.Server.z15-8561.RecommendedService: Usually to fix a defect that is found but haven’t risen up to required. Might want to run an SMP/E REPORT MISSINGFIX to see what’s in this FIXCAT. Might install some, all, or none of the fixes. Might want to be more selective. Based on how much change you want to encounter, versus what problems are fixed
  • By the way there are other FIXCATs you might want to be interested in for z15, e.g. IBM.Function.SYSPLEXDataSharing
Performance - DFSORT And Large Memory
  • A very special guest joins us, Dave Betten, former DFSORT performance lead.
  • Dave talked about DFSORT memory controls
    • DFSORT has historically been an aggressive user of memory
    • Installation defaults can be used to control that
    • But the EXPOLD parameter needs special care - because of what constitutes "old pages", which aren't actually unused.
    • DFSORT Tuning Guide, especially Chapter 3
  • Dave talked about how handy rustling up RMF Overview Reports can be, with several Overview conditions related to memory.
  • Most of the information in this topic is relevant to LPARs of all sizes
Topics - Update on recording techniques
  • Recording of podcast - still using Skype to collaborate
  • Production - Editing - Moved to Ferrite on iPad OS
  • Publishing - same process as before, but on a new publisher!
Customer requirements (assume usual disclaimer)
  • RFE 139477 “Please include the CPU Time Limit for a Job/Step in SMF Type 30”
    • After the fact - End of step looks useful. Could run query comparing to actual CPU time, then track to see if ABEND is on the horizon
  • “ As it happens ” - Would like on the SMF Interval as well as Step End records. May not need the SMF information if vendor and IBM tools already do it today.
On the blog So it goes...
Jul 06, 202056:39
Episode 25 "Flit for Purpose"

Episode 25 "Flit for Purpose"

Here are the show notes for Episode 25 “Flit for Purpose”. The show is called this because it relates to our Topic, and also can be related to our Mainframe topic (as a pun for “Fit for Purpose”).

Mainframe Topic: Highest highlights of z/OS V2.4 and z/OS on z15
  1. Highlight 1:  zCX
  2. Highlight 2: z/OSMF
  • Lots of z/OSMF enhancements that have arrived in z/OS V2.4, and the good news is that most of them are rolled back to V2.3 in PTFs that have been arriving quarterly.
  • Security Configuration Assistant: A way within z/OSMF to validate your security configuration with graphic views, on the user and user group level. Designed to work with all three External Security Managers!
  • Available back to V2.3 with APAR PH15504 and additional group id enhancements in APAR PH17871
  • Diagnostic Assistant for z/OSMF : A much simplier way to gather the necessary information to need for a Service person to perform debug for your z/OSMF problem.
  1. Hightlight 3: SRB on on z15: System Recovery Boost :Speeds up your shutdown for up to 30 minutes and speeds your re-IPL for 60 minutes, with no increase to your rolling four hour average.
Performance Topic: z15 from chip design on upwards
  • Disclaimer: personal view, not from Development or Marketing. Marna and Martin were talking about the z15 Chip design – and we thought those observations might be useful to include in the Performance topic.
  • Two traditional levers were raising clock speed or shrinking the feature size.
  • GHz and nm aren’t the be all and end all. Look at chip design.
  • Start with a similar sized CP chip and putting more on it. It helped to get rid of the Infiniband-related circuits, and some layout enhancements.
  • At the top end there are up to 190 characterisable cores, coming up from 170. This can give us a fifth drawer – which is quite important.
Topic: How To Do A Moonlight Flit
  • This topic is about moving one’s social output, in particular blogs and podcast series. Martin’s blog had to move, because the IBM developerWorks blog site is being shut down.  Martin's blog has had to move, as well as this podcast.
  • Immediately people might worry about Request For Enhancements being affected , and it is not.
  • Martin and Marna discuss important aspects to consider when moving your social media.
  • You must consider all the pieces when do you the most.
  • You must also try to redirect your audience.
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.
Mar 22, 202041:02
Episode 24 "Our Wurst Episode"

Episode 24 "Our Wurst Episode"

Here are the show notes for Episode 24 “Our Wurst Episode”. The show is called this because we both attended the IBM TechU in Berlin, Germany, and our Topics topic is our trip report.

Mainframe Topic: CICS ServerPac in z/OSMF
  • IBM’s first delivery on new installation strategy, will be with CICS and associated SREL products. This is the first of many (really, all).
  • Choice on new installation strategy or old during ShopZ ordering.
  • We encourage making the z/OSMF choice, as that is consistent between IBM and other vendors, and is intended to be easier.
  • Infrastructure already available in continuously delivery PTFs, and rolled back to z/OS V2.2. This makes the driving system have the proper infrastructure so anybody can package and deliver that way.
  • All software that you ordered as a ServerPac, and installed either way, will give you the same (or hopefully better) equivalent installation.
  • There is an IBM Statement Of Direction that this installation choice is coming, but we do not have an exact date yet.
  • For other software ISVs, they can exploit the new z/OS installation strategy whenever they are ready.
  • Prepare now by becoming familiar with z/OSMF Software Management and Workflows
Performance Topic: DB2 And I/O Priority Queuing
  • Follow on from Screencast / Martin's Blog post topic:, "Screencast 12 – Get WLM Set Up Right"
  • Recent talk has been about whether to turn off I/O Priority Queuing in WLM.
  • Service classes with DB2 subsystems in are heavily I/O Sample oriented, which is unusual among service classes in a system.
  • Means access to CPU is not properly managed, as CPU & zIIP samples few, relative to I/O samples. Reminder: Most of DBM1 is now zIIP-eligible.
  • Can achieve goal even with lots of delay for zIIP or CPU, but that’s definitely not what you want.
  • You don’t want to just turn off WLM I/O Priority Queuing, as it’s sysplex-wide, it might affect other work that needs it, and Db2 might actually need it.
  • First you need a reasonably achievable goal for the service class. Make sure you’re more or less achieving the existing goal.
  • Second, calculate what the velocity achieved would be without I/O priority queuing .
  • You should evaluate or adjust the goal attainment, but that is BAU. Changing WLM always needs some care.
Topics: Berlin Trip Report May 20-24
  • We both attended IBM Z TechU in Berlin, and got to see each other.
  • Marna had about six sessions.
    The SMP/E Rookies session had fabulous attendance – 44. Some were more experienced, but most were not.
    z/OSMF had good attendance too, about 82. More are interested in this topic, especially if you compare to just a couple of years ago.
    Best attended was the z/OS V2.4 Preview, with about 150 people. There was excellent interest in what is coming in the new release.
    Marna did her own poster to help with z/OSMF configuration, and several people came by to chat.
  • Both Marna and Martin shared a poster about this podcast. We helped with getting one person a podcast app (on each platform), and a subscription to this podcast.
  • Martin had five sessions.  One was co-written with Anna, “2 / 4 LPARs” Two were solo efforts: Parallel Sysplex Performance Topics, and Even More Fun With DDF.
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.

Mar 22, 202042:34
Episode 23 "The Preview that We Do"

Episode 23 "The Preview that We Do"

Here are the show notes for Episode 23 “The Preview That We Do”. The show is called this because we talk about the newly previewed z/OS release, V2.4, in the Mainframe section. This is our 24th episode too! How convenient!

Mainframe: z/OS V2.4 Preview
  1. “z/OS Container Extensions” (zCX)  zCX Information
  2. z/OS Upgrade Workflow, no book
  3. More in Pervasive Encryption
  4. zFS enhancements
  5. MCS logon passphrases

Biggest question one may have: what level of HW will z/OS V2.4 IPL on? z/OS V2.4 will run on zEC12/BC12 and higher.

Performance: Coupling Facility Structure Duplexing
  • Two types of CF structure duplexing:
    User-Managed: Only DB2 Group Buffer Pools (GBP)
    System-Managed: e.g DB2 IRLM LOCK1 Structure
  • Structure performance matters:
    User-Managed not an issue.
    System-Managed matters.
  • Asynchonous CF Structure Duplexing Announced October 2016
  • Important considerations if Async CF Duplexing good all the time:
    People make architectural decisions and this should not be a leap in the dark .
    Ideally should be established with a little testing, with testing as close to production behaviors as possible.
    Generally it’s good for you.
    Configuration: Format couple data set, put into service, and then REALLOCATE. Again speaks to planning and testing.
  • The main event for this item is SMF.
  • SMF 74-4 Coupling Facility Activity data, primarily interested in structure-level, especially for structure duplexing of any kind. Though CF to CF pathing information also available.
  • New Async CF Duplexing instrumentation APAR OA49148
  • Early days of Async CF Duplexing despite having been announced in 2016. Martin has been using a customer’s test data, and would like to build experience. Only a portion of this new SMF 74-4 data is surfaced in RMF Postprocessor reports.
  • z/OSMF Sysplex Management can help visualize and control the Sysplex resources. This function to help with control is in PI99307: SYSPLEX MANAGEMENT APPLICATION ENHANCEMENTS TO MODIFY SYSPLEX RESOURCES.
Topics: Smart home thermostats

Marna just installed two Nest thermostats, one in each zone (of a three-zone house). Is sharing data with Nest, and presumably whoever owns Nest currently (Google). Instrumentation benefit is having an app in which she can look at what is happening at home, when away, and control it too.

  • There are excellent graphs on what has been used (hours of heating, cooling) in the app.

Martin doesn’t have a smart home thermostat, but does have a remote oil tank sensor to determine how much oil is left. This sensor feeds back into a device in the house, and connects to an app on his phone.

  • It costs 5 GBP a month, but is unsure yet if it is worth it.
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.

Mar 22, 202033:11
Episode 22 "Great App-spectations"

Episode 22 "Great App-spectations"

Here are the show notes for Episode 22 “Great App-spectations”. The show is called this because we talk about app expections in our Topics topic.

PI99365 Two enhancements in z/OSMF Operator Consoles
  1. Support for “sticking” WTOR and held messages on the top of the console area
  2. Visible EMCS console name
  • View WTOR and HOLD messages in a separate window
  • Visible console name part
  • Overall: These two function areas help you manage your z/OSMF operator consoles better.

Performance: Paging Subsystem Design in an age of Virtual Flash
Performance: Paging Subsystem Design in an age of Virtual Flash

  • Question from customer about need for paging space if Flash installed , which was answered in Martin’s blog post, but there is more thinking about this.
  • Look at the paging subsystem design in the round, with two flavours of Flash: FlashExpress (PCIE) and VFM
  • Design standpoint ideally as if no Flash
  • Paging subsystem design: Two main considerations:  Space and Performance
  • Come together in “30% Contiguous Slot Allocation Algorithm breakdown” rule of thumb
  • Instrumentation
    RMF SMF 71, also covers memory. Flash treated like ordinary paging device.
    RMF SMF 74-10 in OA50761
  • Wrap up: Paging subsystem design still worthy of care, and establish whether risk of Flash or Virtual Flash warrants conservative configuration of paging subsystem.

Topics: Anatomy Of A Great App

“App” here means “third party software” but we’ll say app for short

  • Highly biased on expectations in iOS, as Martin is a power user.
  • Marna gave the Android perspective
  • z/OS perspective was discussed.
  • Conclusion: Think about more than just what your app is supposed to do. Nobody wants software whose function they like but they hate using. It is way too easy to uninstall an app (or have hundreds of them and not use them).
    Keep to the “Principle of least astonishment”.
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.

Mar 22, 202042:08
Episode 21 "Fits and Starts"

Episode 21 "Fits and Starts"

Here are the show notes for Episode 21 “Fits and Starts”. The show is called this because we talk about fitness devices, and the Performance topic that had work submitted after a one minute hiatus.

Mainframe: SMF Recording of APF Modifications

Post-IPL dynamic APF changes are reflected in SMF 90 Subtype 37. A lot of the function is in z/OS V2.2, with these fields in the SMF record:

  • Add, Delete, DynFormat, StatFormat
    Was the update via SETPROG, SET PROG, CSVAPF
    Parmlib member suffix for the SET PROG case, ...
  • Triggers when post-IPL APF changes dynamically: PROGxx: APF ADD …or APF DELETE … SETPROG APF,ADD,… or SETPROG APF,DELETE,…
  • Ensure to collect by setting in SMFPRMxx type 90 subtype 37 record
  • Presumably there’s not much overhead, as it will be produced when changes happen (which is probablyl not often).
  • Auditors will probably want this

Performance: An interesting Db2 DDF case

Central to Martin’s DDF work is some analysis code to process SMF 101 DB2 Accounting Trace.

A customer complained their DDF application stopped dead one evening – for 1 minute. It was an application serviced by a 3-way Datasharing group. The customer sent SMF 101 data from all 3 members for 3 hours around the stoppage, and for 3 hours the previous evening for a presumably “good behaviour”.

Martin plotted application statistics at a one second interval level.  It showed a 40-second stoppage the evening they hadn’t complained, making the 1 minute threshold interesting as a number.

Martin “zoomed in” to a much shorter time range . When transactions started again they were elongated, and it that was due to the clustered arrivals in clearing the backlog.

The best theory is something external stopped transactions arriving.

Further he thought there could be “near misses” many times, just short of the 1 minute mark. After transactions started coming again there were spikes in transactions arriving every minute. The speculation is this might be the middle tier doing something on a 1 minute basis: Maybe retries of some sort?

Topics: Fitness Tracking
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.

Mar 22, 202033:17
Episode 20 "Two is One and One is None"

Episode 20 "Two is One and One is None"

Here are the show notes for Episode 20 "Two Is One And One Is None". The show is called this because our Topic topic is trying to figure out how to archive family photos and videos.

 Mainframe: zFS Shrink, Only in z/OS V2.3 

A system command for reducing the size of a zfs file system. Not be confused with compressing files within a file system.  Found on zfsadm shrink. You specify a target size with the size option, gives _final_ size in KB, gets rounded to 8K boundary .

  •  -noai option:  means no active increase.  A file system is being accessed, might need additional blocks over the shrink size given. so it can be "actively increased" by default.  
  • During a shrink a scan occurs to determine what blocks must move...longest part of the operation.  Blocks are moving from the portion to be released, into the portion that is to remain.  
  • After Blocks are moved, and then space is release - in which it will be briefly quiesced. Applications do not need to be stopped when doing a shrink. 

Reminder to use aggrgrow to increase the size of the filesystem. Monitor with SMF 92 subtype 50 for both grow and shrink events.  Subtype 59 for # of I/Os and rate, but might occur too often, so use it wisely.

  Performance:  CPENABLE and HiperDispatch  

  I/O ends with an Interrupt.  Needs to be handled by a processor, and needs to be handled in a timely way.  Can be handled with Test Pending Interrupt (TPI). If test true this CP handles pending interrupt. If false then handled by normal interrupt handling. If many TPI successes suggests queue build up.  Trade off between timeliness and processor efficiency  

There’s a trade off between timeliness and processor efficiency. The CPENABLE parameter’s values manage this trade off. There are two values: if TPI% below first disable a processor from handling I/O interrupts, and if TPI% above second enable a processor to handle them.

Without Hiperdispatch, access to CPU is smeared across online processors, as the LPAR’s weight is evenly spread across its logical processors. Without Hiperdispatch it is recommended that CPENABLE be set to 0,0 which allows all processors to handle interrupts.

Overall this topic shows I/O Interrupt Enablement is a topic worthy of consideration to get timeliness vs efficiency right – particularly in the Hiperdispatch era. Also that the instrumentation really helps.

Topics: Archived Family Information

Talking about personal and family information: photos, audio, and video only. Not writings. Some serious questions:

  • “What happens when I’m dead?” Facebook, for one, has a protocol. Google has a protocol.
  • Ideally write a will and tell family how to handle material.
  • Will anyone else care about the material?
  • “What about Big Brother” : Everyone has something to hide, it’s about trusting the service provider
  • “Who owns the material?” and do you care?
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.

Mar 22, 202036:02
Episode 19 "You've lost that syncing feeling"

Episode 19 "You've lost that syncing feeling"

Here are the show notes for Episode 19 "You've lost that syncing feeling". The show is called this because our Topic topic is about losing the Xmarks URL synchronization tool. 


Our "Mainframe" topic discusses moving from V4 to V5 zFS, prompted by a user comment that had a very positive experience.

  • The old version for zFS was V4.  V5 gives you a directory using a tree structure for faster searching.  This should be faster than a naive linear search approach.  
  • To take advantage of this, you need to convert from old V4 format to V5.  
  • You can convert:  offline with _IOEFSUTL_, online with _zfsadm convert_ , _IOEFSPRM CONVERTTOV5=ON_ , and on _MOUNT_ - you choose.
  • Steps are: ensure fully at V2.1, set _IOEPRMxx format_aggrversion=5_ for new file systems, set _IOEPRMxx change_aggrversion_on_mount=on_ for fast safe file system switch to V5, determine if you want _IOEPRMxx CONVERTTOV5=ON_ for one-time switch on directory access.  Delay is expected!  
  • If cannot tolerate one-time delay, use _MOUNT CONVERTTOV5_ to selectively determine most benefit, on large directories and those highest used (_F ZFS,QUERY,FILESETS_)  
  • Use _zfsadm fileinfo_ to see a directory version, use _zfsadm aggrinfo -long_ to look at all the file systems.  


Our Performance topic is a survey of Licence-Related Instrumentation.  Most shops are very conscious of software costs.   Martin discusses the instrumentation portion.

  • SMF can help you: System-Level SMF 70 give you the rolling 4 hour averages, defined capacity and group capacity information, and high-level CPU . System-Level SMF 89 gives you more detailed information on licencing:  product usage names, and CPU. Service Class Level SMF 72-3 gives you Service Units (SUs) consumed on zIIP, on general purpose CP, and zIIP-Eligible on general purpose CP.
    • Mobile SUs one category and total SUs another 
    • Resource consumption in general . Address Space Level SMF 30 gives you a usage data section for topology and for CPU in a product sometimes.
    • Container-Based Pricing introduces new metrics: 70-1, 89, 72-3, and Tenant Classes and Tenant Resource Groups explicitly documented.

Our podcast "Topics" topic is about Marna losing a handy and simple URL sync tool, XMarks. Xmarks used to let you save bookmarks between browsers with other cool capabilities. It was discontinued on May 1, 2018.  XMarks was a plug-in to browser, logon, sync, and they were there! With multiple profiles.

Here are some ? :

  • NetVibes: better for rss feeds and dashboard seem to be its strength.
  • Google Bookmarks syncs URLs; But still only for Firefox and Chrome. Gmarks will connect to google servers.
  • Modern browsers can fake the User Agent to look like IE
  • Diigo  (at ith a toolbar: not used it. Pricing plans, sharing URLs. A bit too heavyweight/
  • The promising one is called Raindrop (at for Chrome, FF, and Safari. Just started trying it out. Works between Windows and Android!
  • Safari / Mobile Safari use iCloud syncing and work out of the box. But if you share an Apple ID, watch out!
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.

Mar 22, 202026:43
Episode 18 "What we won't have in common anymore"

Episode 18 "What we won't have in common anymore"

Here are the show notes for Episode 18 "What we won't have in common anymore". The show is called this because our Mainframe topic is about some removals in common storage planned for the release after z/OS V2.3. Mainframe

Our "Mainframe" topic discusses a future planned removal coming in the release after z/OS V2.3.


Martin talked about what’s in a data set name and this topic is about getting insight by parsing data set names. His reporting code, which processes SMF 14 (OPEN for read) and SMF 15 (OPEN for write) records, bolds data set qualifiers (or segment names) if they match any of a bunch of criteria. Now, new criteria have been added to investigating data set names.

The new criteria are job step name, dates (in lots of formats), job step program name, “SORT” in the qualifier, and system SMFID.

While the code doesn't see "partner" job names (for instance, where one writes to a data set and the partner reads from the data set), those could be detected using the Life Of A Data Set (LOADS) technique, which we can talk about more one day.

And surely there will be more interesting finds in other customers' data set names. As they are stumbled upon the code can be enhanced to learn these new tricks - as Martin refactored it to make it easier to add new criteria.


Our podcast "Topics" topic is about two cheap and fun pieces of hardware Martin has been playing with: Raspberry Pi and Arduino.

  • Arduino is more hardware oriented. It is an open source hardware board. It is a microcontroller you download small programs to from e.g. a PC, written in a flavour of C. It is optimised for driving electronics, e.g. on a breadboard and boards you plug into the top of the Arduino (called shields).Martin has three Arduino shields: An SD Card reader/writer, a 7-segment display, and graphical LCD display.
  • Raspberry Pi is more for software. It is a small cheap computer on a card.Martin's has 4 USB ports, HDMI, Ethernet, Wifi, and runs Raspbian. You can run other builds. He bought an HDMI monitor for it (HP 27es).He also found a Logitech K780 keyboard and a Logitech M720 mouse. Both of these can be switched instantaneously between 3 computers, connected via Bluetooth or USB.
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.

Mar 22, 202026:35
Episode 17 "Two Good, Four Better"

Episode 17 "Two Good, Four Better"

Here are the show notes for Episode 17 "Two Good, Four Better?". The show is called this because our Performance topic is about aspects of whether more LPARs in the same CECs in a sysplex is better or worse. Mainframe

Our "Mainframe" topic discusses the addition of a new parmlib member for RACF, IRRPRMxx.


Martin talked about whether 2 LPARs (on 2 CECs) or 4 LPARs (on 2 CECs) is better.

  • This is related to some trends, but it's a big subject.
  • There are tradeoffs between 2 vs. 4. Better availability with 4, but would it perform better or worse? It might be better if you get to a state where each LPAR is contained in a single drawer (on z13 or z14). (At least two customers he knows does this.) There is more PR/SM overhead with more LPARs, which was discussed in a 1990 Washington Systems Center Orange book ("PR/SM Performance in LPAR Mode", ZZ05-0453).
  • Also the topic of memory duplication, with more DB2 images. CICS and MQ would similarly have memory considerations too. There might be some scope for consolidation of DB2s.
  • Operational and software considerations need to be thought through. How much harder would it be to manage it, and also keep the software up to date across more images? Of course, much of the thinking would already have been done for 2-way.

Our podcast "Topics" topic is a follow up and a short discussion on what to do if your wifi isn't performing as you wish.

  • It's been a year since Marna's son built his "gaming" personal computer. She asks him about what has gone well with it, and what he might save for in the future.
  • One thing that has been a problem is the wifi signal in the house. It is not consistently strong, and he would like an ethernet connection directly into the computer. That isn't happening (with a cord down the hallway), so a different solution was found: Powerline Ethernet solution, which plugs into two electric outlets.
  • This was less than $100 and is working well. Other solutions do exist, but this cost effective one has been this gamer's delight.
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.

Mar 22, 202030:06
Episode 16 "Chapter and Worse"

Episode 16 "Chapter and Worse"

Here are the show notes for Episode 16 "Chapter and Worse". The show is called this because our Topics topic is about adding chapter markers (and pictures!) to our published MP3 file. We hope those of you that can see them enjoy them. Mainframe

Our "Mainframe" topic discusses a new z/OS V2.3 function, Coupling Facility Encryption, with Mark Brooks, Sysplex Design and Development. Mark talked about this latest capability in Sysplex, which has been getting a lot of attention as part of the larger Pervasive Encryption direction.

Mark explained that CF Encryption means that the customer's data is encrypted by XCF in z/OS, sent along the link as encrypted, and stored as encrypted on the Coupling Facility.

z/OS sysprog needs to set it up by:

  • using new keywords on CFRM policy on a structure by structure basis
  • putting it in your CFRM couple data sets, and the policy change will be pending
  • rebuild the struture (to get it from unencyrpted to encrypted)
  • DISPLAY XCF structure commands can be used to see what the policy has, what the structure currently is, and the form of encryption used.

List and Cache structures contain customer sensitive data, the XCF control information will not be encrypted because it is not sensitive customer data. Lock structures don't contain sensitive customer data, and are not encryptable.


  • zBNA looks at new SMF data, so that you can see the amount of data transferred to the CF. From there, you could judge the cost of doing the encryption.
  • SMF 74 Subtype 4 records contain the new information on the amount of data, via measurement APAR OA51879 on z/OS V2.2. Planning can begin on z/OS V2.2 with this APAR.

For more information, see the z/OS Setting Up a Sysplex.


Martin talked about MSU-related CPU fields for doing software pricing analysis. Some of these fields are used by SCRT in support of the new Mobile function. Most notably the fields cover:

  • Mobile Workload Pricing (MOBILE), using a new WLM mechanism, .
  • CATEGORYA and CATEGORYB: These are just placeholders for any future additional pricing options that come about.

Container Pricing is another pricing model, ....., and maybe another topic on that later.

The overall idea: Be aware of the new fields that you will be analysing. These fields are available at two levels:

  • At the System level, as Rolling 4 Hour Average numbers - in SMF 70 Subtype 1.
  • At the Service Class Period level, as interval-based numbers - in SMF 72 Subtype 3.

Our podcast "Topics" topic is about adding chapter markers to the MP3 file for podcast apps. This makes it nice to skip from one section to another easily. Our podcast has five sections, each with its own graphic and chapter.

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.

Mar 22, 202041:22
Episode 15 "Waits and Measures"

Episode 15 "Waits and Measures"

Here are the show notes for Episode 15 "Waits and Measures". The show is called this because our Performance topic is about LPAR weights, and because this episode was after a seasonal hiatus.


Our "Mainframe" topic discusses a small new function in z/OS UNIX V2.3: automatic unmount of the version "root" file system in a shared file system environment. Our guest was Barry Lichtenstein, the developer of the function, and he told us all about it:

  • there is a new BPXPRMxx VERSION statement parameter, UNMOUNT. This means that when no one is using that "version filesystem", it will be automatically unmounted. This is not the default. Syntax here
  • this function is nice, as it will allow an unused version file system to be "rolled off" when you don't need it anymore. Unused here, means that no system is using it or using any file system mounted under it. z/OS UNIX will do this detection automatically, and unmount not just the version file system, but mounted file systems under it that are no longer used by any systems after an unspecified amount of time.
  • you can turn this on and off dynamically with a SET OMVS or SETOMVS command. There is DISPLAY command support of it. And perhaps the best news, the health check USS_PARMLIB will see if the current settings don't match the used parmlib specification. 
  • we weren't sure if SMF record 92 would be cut when the unmount happened, but Barry said nothing unique was happening for this function so what happens today is most likely the same behavior. There are messages that are issued in the hardcopy log when the unmounts happen. SMF 90 might be issued for SET changes.

Martin talked about Weights and Online Engines in LPARs, and Martin again looking at customer information.

  • Intelligent Resource Director (IRD) changed PR/SM worked:
    1. Dynamic weight adjustment
    2. Online logical engine management (vary online and offline). Shows minimum and maximum weights when changed by IRD.
  • HiperDispatch: took away logical engine management (and manages it better!), and kept IRD dynamic weight adjustment. With HiperDispatch's parking of engines, no work is directed towards it. 
  • More instrumentation was introduced, such as Parked Time and refined instrumentation on weights (vertical weights, by engine).
  • Customer situation was that they did their own version of IRD and HiperDispatch: Varying logical engines online and varying weights (not using IRD itself). Martin expected IRD to change weights, but he saw the IRD weight fields were all zero. 
  • Why not let IRD do it? Martin thinks there was something in the customer's mind to control it themselves.
  • Why not use HiperDispatch? Martin thinks that maybe a subtle difference might be needed, but LPARs should be designed properly. 

Our podcast "Topics" topic was "Video Killed the Radio Star?" and about screencasting.  Martin has been trying to post screencasts to YouTube. Here's one.

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.

Mar 21, 202041:16
Episode 14 "In the Long Run"

Episode 14 "In the Long Run"

Here are the show notes for Episode 14 "In the Long Run". The show is called this because the episode ran much longer than usual, and it is of fitting length if you have a very long commute.


Our "Mainframe" topic is the first in a series of deep dives into z/OS V2.3. Part 1 is on z/OSMF Autostart.

This is the most important migration action in z/OS V2.3, and requires special consideration by every customer IPLing z/OS V2.3. Things that you'll need to consider are:

  • Whether to start z/OSMF or not. (Starting is the default). You control this via IZUPRMxx parmlib members (which in new news can be shared via PI82068).
  • If you don't start z/OSMF and have its functions available to system(s), then you not be able to use certain functions (notably in z/OS V2.3: JES2 Notification).
  • If you don't want to start z/OSMF on a certain system, you can connect to another z/OSMF system in the same sysplex, and that requires specification on which group that would be.
  • The number of z/OSMF servers in a sysplex hasn't changed, still as it was before V2.3.
  • z/OSMF server starting on an LPAR with good zIIP capacity, and memory (minimum of 4GB) is a starting consideration.
  • Strong recommendation: start z/OSMF now on your V2.1 or V2.2 system so that there are fewer work items to do (a couple of security profiles, new procs, parmlib updates only).

In our "Performance" topic Martin talked about two Parallel Sysplex items that he's been pondering extensively recently. He's been using RMF data (taken from SMF type 74 subtype 2 and 4).

Coupling Facility

This is the subject of a blog post: Some Parallel Sysplex Questions, Part 1 - Coupling Facility

  • Resources: CPU, memory, and path
  • Structures: their role to applications, and how responsiveness responds to work load is interesting
XCF Signalling

This is the subject of another blog post: Some Parallel Sysplex Questions, Part 2 - XCF

  • Resources: Paths, buffers, and transport groups
  • Groups: again, knowing the application types, with the theme of managing traffic down when possible

Our "Topics" topic is subtitled "Podcast meets Podcast" with the newest mainframe podcast we know: Terminal Talk.

Frank De Gilio and Jeff Bisti are the hosts, and concentrate on a wider introductory perspective than our MPT podcast does.

  • Terminal Talk (TT) has enviable technology for recording, and came about from Frank and Jeff taking long car rides to Pennsylvania.
  • Planning for the TT podcast consists mostly on engaging guests, and not necessarily following an outline.
  • Length is a big consideration: TT is intended to be of a work-commute length.
  • Editing is done with Audacity, just like our MPT podcast. TT records mono. MPT does stereo. Martin uses the Audacity waveform visualisation when editing; Hence the terms "um fish" and "so so birds". :-)

We had great fun talking to Frank and Jeff; Martin left some of the laughs in the final edit.

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.

Mar 21, 202058:27
Episode 13 "We'll Always Have Paris"

Episode 13 "We'll Always Have Paris"

Here are the show notes for Episode 13 "We'll Always Have Paris". The show is called this because both Marna and Martin reminisce about lovely times in the City of Light.  Marna just got back from Paris with her son (the one that built his own gaming computer). They discuss what they like to do there.


Our "Mainframe" topic discusses what has been a popular item since more people have finished migrating to z/OS V2.2: GDGEs. Generation Data Group Extended (GDGEs) were introduced in z/OS V2.2, and should only be used after fully migrated to that release everywhere. "Old" GDGs allow >255 generations. GDGEs allow up to 999, but with a very different internal structure. GDGEs are externally usable transparently.

There is no straightforward conversion way in DFSMS. Steve Branch (alias name of "Mr. Catalog") and Marna had a six step JCL job to convert (which used IDCAMS ALTERs), and would work if the generations were SMS-managed, which was the initial use case. Several options were discussed.

  • You can do the conversions for your GDGs to GDGEs, but you need to decide if it's worth it.
  • The TSO/e RENAME will work in all the cases that IDCAMS ALTER would, plus more.
  • The shared REXX exec can be used if you want to convert NON_SMS/TAPE GDGs to GDGEs.
  • Still, if you have a gazillion references in places like JCL, it is a compelling case to take some extra one-time work and do the conversion.Mind the recalls! You'll need a lot of recall space on DASD, if you are recalling lots of data sets and they are large.

Martin talked about a presentation he's been keeping updated, Even More Fun With DDF. The original presentation covered: 

  • why you should care about DDF,
  • LPAR to Service Class Level views,
  • side themes of zIIP and DB2 address spaces, and a discussion of SMF 101 and DDF.
  • Contains three different customer cases: some basic statistics, a CPU Spike case, and "sloshing".
  • SMF 30 Enclave Statistics graphing
  • Thoughts on handling clients with huge numbers of short commits
  • Matching client and server DB2 101s where DB2 to DB2 DDF
  • Production vs Feral DDF
  • Diagrams of machines connecting to DB2 via DDF

The updated presentation has an analysis is done using RMF and SMF 30, and SMF 101 DB2 Accounting Trace, using special code written by Martin.

  • Sites: Martin loves to go to the museums. Especially the Louvre and Beaubourg. Marna's son doesn't like museums, so they visit other spots like the Catacombs (with a four hour wait!) and the gargoyles at Notre Dame./li>
  • Food: Marna and her son focus on cheese, and have become quite adept at all three raclette contraptions available, all ways to scrap cheese onto your plate.
  • Getting around: Martin loves the metro, which is so easy and convenient. He loves the part on the metro when you come out from underground to the raised tracks in some places. Marna did a lot of walking. (Fitbit while at Versailles registered 31k steps = 13. miles = 22 km.)
  • Pro Tips: Use the "skip the line" and make reservations very early. Buy tickets early.
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.

Mar 21, 202038:11
Episode 12 "Baker's Dozen"

Episode 12 "Baker's Dozen"

Here are the show notes for Episode 12 "Baker's Dozen". The show is called "Baker's Dozen" because it is the thirteenth episode, after starting at Episode #0.


Our "Mainframe" topic discussed some fun small enhancements Marna has enjoyed from GRS.

  1. With OA42221 back to z/OS R13, GRS has the ability to write SMF records (87 subtype 1) to identify heavy users of global generic queue scans. This is what Marna calls a new "monitoring capability". These issuers might be the cause of increased CPU and GRS private storage. Turn on with GRSCNFxx MONITOR(YES)
    • Existing monitoring of ENQ/DEQs at this point, are not written into SMF records. And the only filtering capability at this point is the old "ISGAUDIT" method. "ISGAUDIT" is a where you prepare you filter, assemble and link edit it into load module and then manipulate it with many MODIFY commands. Not very simple for everyone to do.
  2. With z/OS V2.2, there are two excellent new functions building on OA42221:
    1. SMF 87 subtype 2 records can be written for ENQ/DEQs, and
    2. a new filtering capability available with parmlib member GRSMONxx. There is no IEASYSxx for GRSMONxx, so you must start it with SETGRS GRSMON=xx. Only one GRSMONxx is allowed per system.

Now, you can get all your "monitoring" into SMF records for both ENQ/DEQs and global generic queue scans. And you don't need to use the cumbersome ISGAUDIT anymore.


Martin talked about coupling facility structure performance, especially as it concerns DB2 lock and cache structures. Having a lot of structures isn't a problem, as long as you are looking at how "busy" the coupling facility is - both CPU- and memory-wise. Sorting in descending order the structures by a metric you want is an important and easy way to figure out which structures to pay attention to.

Balance this with the number of DB2 structures to manage - perhaps hundreds! Some advice was given as to what were the most important metrics to concentrate on.

Looking at "false contentions" and "XES contention" for lock structures is important, and may indicate that these structures need to be larger. Especially if the number of false contentions is high, relative to the lock structure requests. For cache structures, there are different metrics. You may have gotten a large number of structures because you are using DB2 data sharing. Look at names and types for a clue as to where they came from.


Our podcast "Topics" topic is how the audio for this podcast gets produced. If you are interested in audio editing, here are some items that recording this podcast has uncovered:

  • For recording: Equipment: Headphones and microphones are necessary. Recording programs: We use Skype with plugins to record.
  • For editing process: Record in chunks, for each podcast section.Audacity is used for the actual editing. Martin places each speaker on a different side (right or left). Audacity makes this very easy.
  • Clean up removes noise, ensures flow, and sound effects are added. Audacity has some nice filters for noise removal, though this isn't 100% perfect.
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.

Mar 21, 202031:43
Episode 11 "XI-Ting"

Episode 11 "XI-Ting"

Here are the show notes for Episode 11 "XI-Ting". The show is called "XI-Ting" because, well, it is episode #11 and we had one shot at the Roman numeral to use and took it. 


Our "Mainframe" topic was Marna's experience in trying out the z/OSMF Workflow Editor. The z/OSMF Workflow Editor is a new function in z/OSMF to create your own Workflow, or change an existing Workflow. The Workflow Editor is available on z/OSMF V2.1 in PTF UI43814 and on z/OSMF V2.2 in PTF UI42847.

  • "Folders" for information you need to provide: Metadata, Variables, Steps, ...
  • You will always have a correctly produced Workflow definition file. Much easier than the old way (Marna used Notepad++ and kept interating).
  • Your first Workflow will probably use a "template" (file like JCL, script, or exec in a step) that you want to drive. You will probably have "variables" (customized values in that template) that you want the Workflow user to specify. Always make sure you associate your variables with the steps! Otherwise they won't coordinate together.
  • The open source Apache Velocity Engine is used for variable substitution and conditional directives.
  • There is a very small checkbox for resolving variable substitution in the Workflow Editor. Don't forget to check it if you are using variables!
  • Remember to remove the first "dummy" step when creating a Workflow from scratch. You don't need it.

Martin had a special guest for a conversation on zHyperLinks, Anna Shugol, IBM Mainframe Technical Specialist. Martin and Anna talked about a Statement of Direction that was released at the beginning of 2017. 

This topic is very important because it is an innovative new IBM I/O and Storage technology to improve performance for DB2-centric applications. This is designed to provide dramatic improvements in I/O latency, and change the I/O paradigm. It complements existing technology, such as Hiper Performance FICON and using large DB2 buffer pools. zHyperlinks is intended to provide short distance (150 meters between the CEC and the storage unit) point-to-point improvements, which are expected to support 8GBs (gigabytes per second) with new protocols.

  • Today, there is I/O to the Coupling Facility, and FICON to disk and tape and times associated with those. zHyperlinks is planned to support improvements in the connect and pend times, with Sync I/O wait times being the dominant DB2 components helped with zHyperlinks.
  • The IBM Storage device required for this solution will be a minimum of DS8880, with up to 16 zHyperLinks being able to be connected.
  • The minimum z/OS and DB2 levels will be provided later.

Our podcast "Topics" topic has been sub-titled "Some Assembly Required" ; Not the HLASM that mainframers might think that relates to, but actually something in the same vein. Marna's 14-yr old son who is interested in hardware has just built his first personal computer. Marna and Martin talk about how that first computer has a lot in common with a mainframe.

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.

Mar 21, 202034:48
Episode 10 "234U"

Episode 10 "234U"

Here are the show notes for Episode 10 "234U". The show is called "234U" because:

  • We are very happy that we can talk about z/OS V2.3 now that it's been previewed on February 21, 2017.
  • We liked the consecutiveness 2-3-4, and U added works nicely.

Our "Mainframe" topic was a highlight of some of the newly previewed z/OS V2.3 enhancements! We will surely talk a lot about z/OS V2.3 in podcasts to come.

First, it is important to know that z/OS V2.3 will only IPL on an zEC12, zBC12 and higher. Prepare now if you need to.

Here's a brief list of the items planned for V2.3 (which is planned to GA on September 29, 2017)

  • System logger's log stream staging datasets can be allocated greater than 4 gigabytes.
  • Data set encryption for z/OS data sets and zFS file systems (policy-enabled), and CF structures (list and cache, with the CFRM policy).
  • zFS:
  • zEDC compression on individual files, and existing and new zFS files systems. Existing zFS while in use!
  • Salvage utility to run online with file system is still mounted
  • Dynamic changes to aggregrate attributes for common MOUNT options, and dynamic changes to sysplex sharing status.
  • New facility (from TSO or UNIX shell) to allow for migration from HFS to zFS, without requiring the "from" file system to be unmounted.
  • email: ability to have an email address in the RACF user profile. JES2 and z/OSMF could use email notification to the user.
  • JES2 JCL, the delimiter keyword (DLM) on SYSIN is extended from 2 to 18 characters long.
  • SCRT is a component delivered in z/OS, with support for enabling ISVs to generate an ISV-unique SCRT report.
  • Auto-starting z/OSMF be default, late in the IPL hopefully after OMVS and TCP/IP are up. The biggest migration action in z/OS V2.3 identified yet.
  • TSO/E support for 8 character userids. Many products require changes to support this, so do planning for this one.


Martin had an esteemed guest for our "Performance" topic, Elpida Tzortzatos, Distinquished Engineer from z/OS Development.

Martin and Elpida chatted about several important recent advances made in the area of z/OS memory management.

Use the LFAREA specification for 1MB and 2GB frame usage.

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.

Mar 21, 202053:31
Episode 9 "Back in Black"

Episode 9 "Back in Black"

Here are the show notes for Episode 9 "Back in Black". The show is called "Back in Black" because:

Continuous Delivery Follow-up Announcements


Our "Mainframe" topic was an interview with John Eells, z/OS System Test and lead on the Software Installation Strategy.

This topic is very important for z/OS system programmers to understand. IBM and ISVs have been working on a common install method, that handles both SMP/E and non-SMP/E. This would go beyond laying down code, and would eventually hook seamlessly into doing configuration tasks (via z/OSMF Workflow). It would even be able to package software, if you wanted to, and all delivered within the base z/OS operating system.

The common install method would be provided through z/OSMF's Software Management plug-in, so make sure you are setting up and becoming familiar with z/OSMF now. John and Marna also talked about some of the wishlist items we'd like to see in this solution.


Our "Performance" topic was about some about additions and changes to Martin's Parallel Sysplex Performance presentation that he's been presenting over the years. Somehow this presentation never seems to get any shorter.

This presentation has several sections: Structure-Level CPU, Matching CF and PR/SM views of CPU, Structure Duplexing, XCF traffic, CF link information, and CF Thin Interrupts.

The new parts and changes he has made in this presentation are:

  • Asynchronous Duplexing for lock structures. You can also find a good Mainframe Insights article about this by David Surman here.
  • XCF traffic and Data Sharing Group topology


  • CF Thin Interrupts and CPU.

Ahoy! In our "Topics" section we discuss voice-activated assistants that have been hitting the market for a while now.

Martin has a good amount of experience in Siri from Apple and Alexa (Amazon) Echo and Dot. A third one is Google Home.

Martin talks about the various pros and cons on each.

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.

Mar 21, 202036:28
Episode 8 "Queue Me Up"

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:


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.


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.


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.

Mar 21, 202032:17
Episode 7 "We Were On a Break"

Episode 7 "We Were On a Break"

Here are the show notes for Episode 7 "We Were On a Break". The show is called "We Were On a Break" because:

  • It's been a very long time since we last recorded an episode. You should read nothing into other than our schedules and, in particular, Martin's long holiday put paid to recording for a while.

    But now we're back...

We had one piece of follow up:

  • IBM Doc Buddy - available for iOS and Android.

    This app has been enhanced with new components (aka libraries) and has received some fixes that users have found. There's a very reponsive team working on this tool! This app is now better than the old LookAt tool, since reason codes can be searched.


Our "Mainframe" topic was a discussion on Continuous Delivery.

Marna talked about four important references to understand what the z/OS platform is doing for Continuous Delivery. (IBM is embracing Agile development for many new functions, and will be providing those functions to customers in a Continuous Delivery method.)

Takeaway: some products will be putting their new functions in the service stream, while others might be putting them in releases. Read announcements carefully to see which of your products is following which model. Performance

Our "Performance" topic was an extension of this blog post of Martin's: Why Do We Keep Building Bigger Machines?

We acknowledge this is quite a high level treatment but it's a question that we're sure has been in the back of lots of minds. We've ideas to take some of the subtopics and make them topics in their own right.


In our "Topics" section we discussed what we (especially Martin) are using for creating presentations these days.

Products Martin mentioned were:

Interesting Customer Requirements

Here's two customer requirements we've taken notice of. Of course, IBM may or may not decide to do them, but they might be interesting if you'd like to vote on them.

  • "zFS Definitions of Greater Than 4 GB Not Being SMS-Managed Should be Available Under IDCAMS", ID 92523

  • "Let IBM Knowledge Center search within a manual and simplify the use", ID 93288 .

Contacting Us

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

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

Mar 21, 202035:13
Episode 6 "Expect the Unexpected"

Episode 6 "Expect the Unexpected"

Here are the show notes for Episode 6 "Expect The Unexpected".  The show is called "Expect The Unexpected" for two reasons: 

  • We really didn't expect to be recording an episode in this timeframe.
  • The Performance topic lends itself to such a title.

We had one piece of follow up:  


Our "Mainframe" topic was a discussion on IBM Doc Buddy - available for iOS and Android. It's a tool for looking up error messages and is now enhanced with z/OS Unix Reason Codes. It enables retrieving z Systems message documentation and provides the allows you to look up message documentation without Internet connections after downloading desired files. It's available for z/OS, as well as other products like CICS, and IMS, and for many releases of those products. 


Our "Performance" topic was about what happens when unexpected work appears on your beloved mainframes. A number of themes were discussed, including: 

  • Not knowing mobile workload was appearing - leading to potential loss of savings on Mobile Workload Pricing.
  • When unannounced work arrives, leading to implications for e.g. Security, Performance Management, and Capacity Provisioning.

In reality how you handle this is a governance and culture question, but we want you to think about the problem.


In our "Topics" section we discussed two items: 

  • iTunes - where you can now find our podcast here. We hope some of you find this new way to subscribe easier.
  • Liberated Syndication (or LibSyn for short). This gives us some interesting statistics about our listenership.
On The Blog

Martin posted to his blog, since our last episode:

Contacting Us

You can reach Marna on Twitter as mwalle and by email

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

Mar 21, 202018:40
Episode 5 "The Long Back from Munich"

Episode 5 "The Long Back from Munich"

Here are the show notes for Episode 5 "The Long Road Back From Munich".  The show is called "The Long Road Back From Munich" because we've both returned from a successful z Systems conference 2016 IBM z Systems Technical University, 13 - 17 June, Munich, Germany


Our "Mainframe" topic was Marna's conference observations:

  • IBM HTTP Server Powered by Apache: it seemed about 30-40% were impacted by the move from the Domiino to Apache server. More than hoped, but if you work on it while on z/OS R13 or V2.1, you'll be well-positioned for z/OS V2.2.
  • zEvent sessions: Martin and Marna both went to Harald Bender's zEvent session where he discussed using your mobile device (either Apple or Android) to receive timely information about events on your z/OS system. The handouts are here: zEvent and z/OS Console Messages to Your Mobile Device . This app was so easy to download and start using, Martin did just that during Harald's session!
  • z/OSMF: Marna was happy with the interest in z/OSMF, and with the z/OSMF V2.2 enhancements rolled back into z/OSMF V2.1 in PTFs from January 2016 PTF UI90034.There is no reason to delay using it. The z/OSMF lab for SDSF, however, had a problem as CEA had gotten its TRUSTED attribute removed somehow before Munich. After it was made TRUSTED (after the conference), everything was fine again. Goes to show how important the security settings are for z/OSMF!
  • z/OS V2.2: Good interest in the release. Happy to see so many people already running z/OS V2.
  • Secure electronic delivery: Since regular FTP for electronic delivery was removed on March 22, 2016, only secure delivery is available. No one at the conference said they were impacted, which was nice to see.

Our "Performance" topic was Martin's conference observations:

  • State Of SMT Instrumentation Knowledge: Simultaneous Multi Threading (SMT) metrics are not well understood at this point. Customer data from turning on SMF (for both zIIP and IFL) is starting to appear on Martin's desk. The good news is that the pickup on this function is fast.
  • His Presentations: Martin's sessions were nicely attended. Martin is continuing with his fun at looking at DDF, and "He Picks on CICS" might have more information to be added in the future.

The presentations can be found on Slideshare. 


In our "Topics" section we discussed various other conference observations:

  • Martin presented sessions from his iPad.: Although a lot of cables had to be carried around, it did work fine. He even used his Apple Pencil to mark on the slides during his presentations. So he might never lug a laptop to a conference again. Famous last words!
  • Conference poster sessions: What a success! Martin & Marna had a poster about...wait for it...this podcast. Martin was very busy talking to people who were interested in our poster. Marna also had a poster on using MyNotifications for New Function APAR notification:
Contacting Us

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

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

Mar 21, 202027:02
Episode 4 "The Road to Munich"

Episode 4 "The Road to Munich"

Here are the show notes for Episode 4 "The Road To Munich".  

The show is called "The Road To Munich" partly in homage to the Road To... movies and partly because we're preparing for the 2016 IBM z Systems Technical University, 13 - 17 June, Munich, Germany


Our "Mainframe" topic was on a small z/OS V2.1 enhancement that few seem to be using: SMFPRMxx's AUTHSETSMF. This new option controls whether you want to allow use of the SETSMF command, different from the SET SMF command, without tying it anymore to the specification of PROMPT. Exploiting this function is as easy as adding AUTSETSMF to your SMFPRMxx for the next IPL!


Our "Performance" item was a discussion on another of Martin's "2016 Conference Season" presentations: "He Picks On CICS".


Following up the Episode 3 "Topics" item on iThoughts and Mind Mapping, Martin wrote up how to make a (colour-coded) legend in iThoughts The Legend on his blog.  


Martin's latest blogs:

Mar 21, 202023:15
Episode 3 "Getting Better"

Episode 3 "Getting Better"

Here are the show notes for Episode 3 "Getting Better". 

Follow Up
  • Following up the Episode 1 "Topics" item on Markdown, Martin talked about John Gruber's Daring Fireball Dingus page which lets you paste in Markdown and see the HTML generated from it (and how the HTML is rendered).
  • Also following up on an Episode 1 item, but this time the "Mainframe" item, Marna talked about her personal problem with ISPF 3.17 Mount Table right / left she was seeing before. It was the PF key definition (which she suspected all along), however defining 12 PF keys did the trick.

Our "Mainframe" topic included our first guest, Glenn Wilcock, a DFSMS architect specializing in HSM. Glenn talked about a very important function - using zEnterprise Data Compression (zEDC) for HSM. He discussed some staggering excellent numbers for CPU reduction, throughput improvement, and storage usage reduction. A win on all three fronts. Here are some of the links that you can use to get more information about this topic


Our "Performance" item was a discussion on one of Martin's "2016 Conference Season" presentations: "How To Be A Better Performance Specialist". Two particular points arising: We'll publish a link to the slides when they hit Slideshare, probably after the 2016 IBM z Systems Technical University, 13 - 17 June, Munich, Germany.

  • This presentation might interest a wider audience than just Performance and Capacity people.
  • You might get something out of it even if you've been around for a while.

Under "Topics" we discussed mind mapping and how we use it for this podcast and other uses, such as depicting relationships between CICS systems and the DB2 subsystems they attach to. Martin mentioned Freemind, an open source cross-platform mindmapping tool, available from here. He also mentioned the proprietary iThoughts, which has an iOS Version and a macOS version. Data is interchangeable between these two and Martin uses both versions, with the iOS version on his iPad Pro and his iPhone. 

On The Blog Martin posted to his blog: 

On z/OS Marna posted to her blog:

  • Are you electronic delivery secure?. Warning!!! Regular old ftp for electronic software delivery will be gone on May 22, 2016, for Shopz and SMP/E RECEIVE ORDER. Find a secure replacement.
Contacting Us  

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

Mar 21, 202028:29
Episode 2 "Sound Affects"

Episode 2 "Sound Affects"

Here are the show notes for Episode 2 “Sound Affects

We had some follow up items.  As you can see we do actually pay attention to feedback and follow it up when we can. So keep sending it in. 


Our “Mainframe” topic is about blocking the IBM Ported Tools product for ordering with z/OS V2.2. You don’t need IBM Ported Tools V1.3 product with z/OS V2.2 since the same functions are contained in the operating system now at either the same or higher level. For z/OS V2.2 contents look here, searching in the page for “OpenSSH” or “Apache”.


 Our “Performance” topic is about Coupling Facility Link Latency, which sounds like a boring topic. It actually has its own share of thrills and spills. 


Under “Topics” we discussed the Android app “Smart Maps Offline”. This handy tool can save you mobile data costs if you are directionally challenged. Maps are free for Android, but might cost for Apple’s version of this app. Good bits were: personal pins can be added, common points (hotels, restaurants, transportation) is already marked, good performance, small download map size. Things we’d like to see improved: can’t give you directions to somewhere, and maps are in the local language only. See your app store for downloading this handy tool. One such place is here


Martin has blogged on it several times: 

Contacting Us

You can reach Marna on Twitter as mwalle and by email. You can reach Martin on Twitter as martinpacker and by email. Or you can leave a comment below.

Mar 21, 202026:41
Episode 1 “A Luta Continua” (“The Struggle Continues”)
Mar 21, 202030:32
Episode 0 “Sic Parvis Magna” (“Greatness From Small Beginnings”)

Episode 0 “Sic Parvis Magna” (“Greatness From Small Beginnings”)

Here are the show notes for Episode 0 “Sic Parvis Magna” (“Greatness From Small Beginnings”). 

We’re structuring each podcast episode (loosely) in three parts: 

We’ll post useful links and supplementary information in each episode’s show notes.  Other things we discussed were: And if you think Naughty Dog made up “sic parvis magna” see here.  Mainframe

Our “Mainframe” topic is about an SPE to z/OS 2.1 for SDSF. APARs mentioned were:

z/OS 2.1 SDSF SPE Performance

Our “Performance” topic is about detecting address spaces in support of FPGA cards. Some useful information on the new PCIE and FPGHWAM address spaces is here. (FPGA Card Support Address Space Detection).

Topics Contacting Us

You can reach Marna on Twitter as mwalle and by email. You can reach Martin on Twitter as martinpacker and by email. Or you can leave a comment below.

Mar 21, 202013:17