All About zIIPs

If you work with Db2 then you need to know about the IBM zIIP specialty processor. This is true whether you are a DBA or a developer... and, let's face it, if you work on a mainframe in any capacity, you'll want to know at least something about zIIPs.

With that in mind, today's blog post is sort of a meta-post. You see, I've been writing a series of blog posts for Cloudframe on the topic of zIIPs. So, the goal today is to provide you with information about those posts and links to their content.

The first blog post, Understanding Mainframe Specialty Processors: zIIPs and More, is introductory in nature. It defines the term "specialty processor" and defines the various types of specialty processors available from IBM. And then it offers a bit more information about the zIIP.

The second post in this series is titled Digging Into the zIIP: What Does zIIP-Eligible Mean? The title is kind of self-describing as to what this post offers!

Next (3 of 8) we have Types of Processing That Can Utilize zIIPs & Why You Want to Use zIIPs which gets into TCBs and SRBs, enclaves, and discusses how zIIPs can reduce your mainframe software costs.

The fourth post in this series digs into one of the major benefits of zIIPs, namely the ability to run Java workloads on the zIIP. In the article, titled Java and the zIIP: Five Major Benefits, we look at the primary advantages that can be accrued by running Java on zIIPs instead of a general purpose CP.

And because the vast majority of mainframe programs are written in COBOL the fifth post, provides Options for Converting from COBOL to Java.

Next, we take a look at Common zIIP Usage Mistakes and How to Identify Them.

Then we turn our attention to the latest IBM pricing model, Tailored Fit Pricing, and examine how it can impact cost savings when it comes to zIIP usage. This post is titled, appropriately enough, The Impact of Tailored Fit Pricing on zIIPs.

And we close out with Predictions on the Future of zIIP and Specialty Processors (of course, this is my personal viewpoint on the topic with the proviso that nobody knows the future for sure)!

So it is my hope that you will take a moment or two and click through the links to the articles above that look interesting to you. And if you have any comments, or suggestions for future articles, as always, please post them below!

My Speaking Schedule at IDUG Db2 Tech Conference in Boston (2022)

 Just a quick note to let everybody who is coming to Boston in July for IDUG know what I will be speaking about and when my presentations are scheduled!

First of all, my regular IDUG session this year is titled "Things Your DBAs Hear... and how to stop making them crazy!" This session is based on my decades of experience as a DBA and as a consultant. This session walks you through interactions between developers and DBAs, in a light-hearted way. All of them are real-life examples of actual conversations I've been in (or observed).  Attend this session to learn what frustrates DBAs and how improving your communication can improve your relationship with your DBAs... and therefore improve your development  efforts!  This is session E11, and it will be delivered on Wednesday, July 13 at 11:30 AM.

I will also be presenting at two different VSP sessions, one on Tuesday and another on Wednesday (this is the 10:15 AM time slot on both days).

On Tuesday, I will be presenting with InfoTel on the topic "To Protect and Preserve: Treat Your Data Properly or Pay the Consquences." This session will discuss vital data management issues such as data archiving and data protection (my portion), as well as some products that can help you manager your data better (the InfoTel portion). 

On Wednesday, I will be presenting "How to Accelerate Db2 SQL Workloads... Without Db2!" for Log-On Software. This session takes a look at in-memory trends and issues, and shines a light on how QuickSelect can improve the performance of SQL queries.

I hope to see you at this year's IDUG North American conference the week of July 11, 2022. If you are there, come see one (or all) of my sessions... and be sure to say "Howdy!"

Time to Download the Db2 13 for z/OS Manuals!

Yesterday I posted a brief piece about the new version of Db2 for z/OS that is now generally available: Db2 13 for z/OS is Here! It is always an exciting time when a new version of Db2 for z/OS is unleashed on the world and one of the first things I recommend is to start reading the manuals to see what all is there!

I like having the PDF versions of the manuals on my hard drive, so with each new version, I start by downloading them! With that in mind, here is the link to the IBM page that hosts the PDF manuals for Db2 13 for z/OS. 

Of course, over time, this documentation will be modified. Therefore, it is a good idea to be aware that subsequent modifications may render the versions on your hard drive inaccurate. You can always replace them periodically if you wish... perhaps when you adopt a new function level make plans to downloads the latest iterations of the manuals. 

There is also a great, new redbook on Db2 13 for z/OS that you should download and read. It is titled IBM Db2 13 for z/OS and More, and it, along with the What's New manual, can serve as a nice introduction to this new version.

A new manual that I need to mention is the SQL Data Insights Users Guide. If you read my earlier post (Db2 13 for z/OS is Here!) then you know that SQL Data Insights is a new Db2 13 capability that combines AI/deep learning with Db2 for z/OS and IBM Z technologies to deliver SQL-based semantic queries on tables and views. It is probably one of the most exciting new things in this new version...

So if you work with Db2 for z/OS don't delay... download those new manuals and start learning what new wonders Db2 13 will offer up!

Db2 13 for z/OS is Here!

Here we are, in June 2022, about 5 years or so since Db2 12 for z/OS was released. And lo' and behold, IBM has given us a new version of Db2 for z/OS to learn and adopt: Db2 13 for z/OS. 

The new version is generally available (as of May 31, 2022). If you were not paying close attention though, you may have missed it. Db2 13 was announced at the same time as the new mainframe (IBM z16), so it didn't get quite the same level of attention. But those of us who use Db2 for z/OS day in and day out will find a lot of great new stuff in this latest and greatest version of Db2.

I'm not going to go into great detail about the new features and functionality of Db2 13 for z/OS today, but I will offer a high-level overview. Look for future blog posts to dig into more of the nitty gritty tech details and capabilities.

The first thing to mention is that you will need to activate the last Db2 12 function level 510 (FL510) before you can migrate to Db2 13. As many organizations are lagging behind in terms of function level activation, it will be interesting to see how this requirement impacts migration to Db2 13.

AI

So what can users expect from this new version? Well, it seems that the most talked-about features are related to adopting AI. Functions that deliver AI capabilities into Db2 will make it easier for organizations on the AI journey to integrate Db2 into their processes.

Perhaps the most significant AI addition to Db2 13 is the SQL Data Insights feature. Provided as an extension to Db2, SQL Data Insights is delivered using built-in functions to deliver AI capabilities like uncovering heretofore unknown relationships in your data. Since it uses built-in functions you can use it anywhere that you use SQL!

Db2 13 offers additional AI help delivering the ability to simplify building models, Natural Language Processing (NLP), and exploiting the speed of the IBM z16 for training and querying data.

IBM z16 Synergy

The next thing that has been highly-touted is that Db2 13 takes advantage of new capabilities delivered in the IBM z16 hardware.  The new Telum chip used by the z16 mainframe provides powerful AI capabilities that Db2 uses to bolster its AI capabilities (such as SQL Data Insights). And we have already touched on that in terms of speeding up training and querying data for AI.

Db2 for z/OS is unique in that it is the only major DBMS that is designed specifically for a single operating system (z/OS) and hardware platform (IBM Z). This enables IBM (the provider of the DBMS, O/S, and hardware) to take advantage of capabilities unique to the platform, because there is no worry about supporting other platforms.

One example of this unique synergy is the ability to improve sort performance using the SORTL instruction of the IBM Z15 and z16. Additionally, the IBM z16 System Recovery Boost can minimize downtime by speeding up the performance of Db2 for z/OS restart. 

But What About BAU?

OK, so there is new AI stuff and great synergy with the IBM Z, but what about the features and functionality that make it easier to keep up with Business As Usual (BUA)? You know, things like easier administration, better performance, and so on?

Good news! There are a plethora of great new capabilities and improvements in Db2 13 for z/OS. While I cannot adequately cover them in detail today, some examples include:

• The ability to convert back-and-forth between partition-by-growth and partition-by-range Db2 table spaces. 
• Support for more concurrent threads and open data sets, as well as improved storage conditions. 
• DDF storage relief.
• Real Time Statistics (RTS) improvements.
• Many improvements to IBM Db2 utility functionality.
• Security and compliance improvements, including integration to the IBM Z Security and Compliance Center.

Summary

The bottom line is that there is a new version of Db2 for z/OS that mainframe shops will need to learn and prepare for. As with any new Db2 version, it will be exciting to dig in and discover all of the new stuff that can help us do our jobs better... and improve our organization's efforts to use its data to improve business.

Keep checking back here as I will blog in more detail about the new capabilities of Db2 13 for z/OS over time... 

TCBs, SRBs, and Enclaves

Many Db2 DBAs first hear about Task Control Blocks (TCBs) and Service Request Blocks (SRBs) in an IBM performance class, but not everyone has taken one of those classes. And even for those who have, a refresher is probably in order.

At a high level, for mainframe z/OS programs code can execute in one of two modes: TCB mode, also known as task mode, or SRB mode. Most programs execute under the control of a task. Each thread is represented by a TCB. A program can exploit multiple processors if it is composed of multiple tasks, as most programs are.

An SRB is a control block that represents a routine that performs a particular function or service in a specified address space. SRBs are lightweight and efficient but are available only to supervisor state software. An SRB is similar to a TCB in that it identifies a unit of work to the system. But an SRB cannot “own” storage areas. SRB routines can obtain, reference, use, and free storage areas, but the areas must be owned by a TCB. SRB mode typically is used by operating system facilities and vendor programs to perform certain performance-critical functions.

In general, z/OS dispatches Db2 work in TCB mode if the request is local, or in SRB mode if the request is distributed. These parallel tasks are assigned the same importance as the originating address space. Of course, this is a gross generalization and as zIIPs have become ubiquitous more SRB mode work has been enabled (as only SRBs can run on the zIIP).

Preemptible enclaves are used to do the work on behalf of the originating TCB or SRB address space. Enclaves are grouped by common characteristics and service requests, and because they are preemptible, the z/OS dispatcher—and Workload Manager—can interrupt these tasks for more important ones. There are two types of preemptible SRBs: client SRBs and enclave SRBs.

If the Db2 request is distributed DRDA workload, then it will be executed in enclave SRBs. If the request is coming over a local connection, then it will be dispatched between TCBs, client SRBs, and in some cases enclave SRBs (such as for parallel queries and index maintenance).

What Is an Enclave?

An enclave is a construct that represents a transaction or unit of work. Enclaves are a method of managing mainframe transactions for non-traditional workloads. You can think of an enclave as an anchor point for resource accumulation regardless of where the transaction is executing.

With traditional workloads, it is relatively easy to map the resources consumed to the actual transaction doing the consumption. But with non-traditional workloads (such as web transactions, distributed processing, and so on) it can be more difficult because a transaction can span multiple platforms. Enclaves are used to overcome this difficulty by correlating closely to the end user’s view of the transaction.

So even though a non-traditional transaction can be composed of multiple “pieces” spanning many server address spaces, and can share those address spaces with other transactions, the enclave gives you more effective control over the non-traditional workload. 

Synopsis

Hopefully this short introduction to TCBs, SRBs, and Enclaves has been helpful. At least the next time you hear somebody use these terms you'll have some idea what they are talking about!