IBM z14: Pervasive Encryption & Container Pricing

On 17 July 2017 IBM announced the z14 server as “the next generation of the world’s most powerful transaction system, capable of running more than 12 billion encrypted transactions per day.  The new system also introduces a breakthrough encryption engine that, for the first time, makes it possible to pervasively encrypt data associated with any application, cloud service or database all the time”.

At first glance, a cursory review of the z14 announcement might just appear as another server upgrade release, but that could be a costly mistake by the reader.  There are always subtle nuisances in any technology announcement, while finding them and applying them to your own business can sometimes be a challenge.  In this particular instance, perhaps one might consider “Persuasive Encryption & Contained Pricing”…

When IBM releases a new generation of z Systems server, many of us look to the “feeds and speeds” data and ponder how that might influence our performance and capacity profiles.  IBM state the average z14 speed compared with a z13 increase by ~10% for 6-way servers and larger.  As per usual, there are software Technology Transition Offering (TTO) discounts ranging from 6% to 21% for z14 only sites.  However, in these times where workload profiles are rapidly changing and evolving, it’s sometimes easy to overlook that IBM have to consider the holistic position of the IBM Z world.  Quite simply, IBM has many divisions, Hardware, Software, Services, et al.  Therefore there has to be interaction between the hardware and software divisions and in this instance, IBM have delivered a z14 server that is security focussed, with their Pervasive Encryption functionality.

Pervasive Encryption provides a simple and transparent approach for z Systems security, enabling the highest levels of data encryption for all data usage scenarios, for example:

  • Processing: When retrieved from files and processed by applications
  • In Flight: When being transmitted over internal and external networks
  • At Rest: When stored in database structures or files
  • In Store: When stored in magnetic storage media

Pervasive Encryption simplifies and reduces costs associated when protecting data by policy (I.E. Subset) or En Masse (I.E. All Of The Data, All Of the Time), achieving compliance mandates.  When considering the EU GDPR (European Union General Data Protection Regulation) compliance mandate, companies must notify relevant parties within 72 hours of first having become aware of a personal data breach.  Additionally organizations can be fined up to 4% of annual global turnover or €20 Million (whichever is greater), for any GDPR breach unless they can demonstrate that data was encrypted and keys were protected.

To facilitate this new approach for encryption, the IBM z14 infrastructure incorporates several new capabilities integrated throughout the technology stack, including Hardware, Operating System and Middleware.  Integrated CPU chip cryptographic acceleration is enhanced, delivering ~600% increased performance when compared with its z13 predecessor and ~20 times faster than competitive server platforms.  File and data set encryption is optimized within the Operating Systems (I.E. z/OS), safeguarding transparent and optimized encryption, not impacting application functionality or performance.  Middleware software subsystems including DB2 and IMS leverage from these Pervasive Encryption techniques, safeguarding that High Availability databases can be transitioned to full encryption without stopping the database, application or subsystem.

Arguably IBM had to deliver this type of security functionality for its top tier z Systems customers, as inevitably they would be impacted by compliance mandates such as GDPR.  Conversely, the opportunity to address the majority of external hacking scenarios with one common approach is an attractive proposition.  However, as always, the devil is always in the detail, and given an impending deadline date of May 2018 for GDPR compliance, I wonder how many z Systems customers could implement the requisite z14 hardware and related Operating System (I.E. z/OS) and Subsystem (I.E. CICS, DB2, IMS, MQ, et al) .upgrades before this date?  From a bigger picture viewpoint, Pervasive Encryption does offer the requisite functionality to apply a generic end-to-end process for securing all data, especially Mission Critical data…

Previously we have considered the complexity of IBM z Systems pricing mechanisms and in theory, the z14 announcement tried to simplify some of these challenges by building upon and formalizing Container Pricing.  Container Pricing is intended to greatly simplify software pricing for qualified collocated workloads, whether collocated with other existing workloads on the same LPAR, deployed in a separate LPAR or across multiple LPARs.  Container pricing allows the specified workload to be separately priced based on a variety of metrics.  New approved z/OS workloads can be deployed collocated with other sub-capacity products (I.E. CICS, DB2, IMS, MQ, z/OS) without impacting cost profiles of existing workloads.

As per most new IBM z Systems pricing mechanisms of late, there is a commercial collaboration and exchange required between IBM and their customer.  Once a Container Pricing solution is agreed between IBM and their customer, for an agreed price, an IBM Sales order is initiated, triggering the creation of an Approved Solution ID.  The IBM provided solution ID is a 64-character string representing an approved workload with an entitled MSU capacity, representing a Full Capacity Pricing Container used for billing purposes.

Previously we considered the importance of WLM for managing z/OS workloads and its interaction with soft-capping, and this is reinforced with this latest IBM Container Pricing mechanism.  The z/OS Workload Manager (WLM) enables Container Pricing using a resource classified as the Tenant Resource Group (TRG), defining the workload in terms of address spaces and independent enclaves.  The TRG, combined with a unique Approved Solution ID, represents the IBM approved solution.  As per standard SCRT processing, workload instrumentation data is collected, safeguarding that this workload profile does not directly impact the traditional peak LPAR Rolling Four-Hour Average (R4HA).  The TRG also allows the workload to be metered and optionally capped, independent of other workloads that are running collocated in the LPAR.

MSU utilization of the defined workload is recorded by WLM and RMF, subsequently processed by SCRT to subtract the solution MSU capacity from the LPAR R4HA.  The solution can then be priced independently, based on MSU resource consumed by the workload, or based upon other non-MSU values, specifically a Business Value Metric (E.g. Number of Payments).  Therefore Container Pricing is much simpler and much more flexible than previous IBM collocated workload mechanism, namely IWP and zCAP.

Container Pricing eliminates the requirement to commission specific new environments to optimize MLC pricing.  By deploying a standard IBM process framework, new workloads can be commissioned without impacting the R4HA of collocated workloads, being deployed as per business requirements, whether on the same LPAR, a separate LPAR, or dispersed across multiple LPAR structures.  Quite simply, the standard IBM process framework is the Approved Solution ID, associating the client based z/OS system environment to the associated IBM sales contract.

In this first iteration release associated with the z14 announcement, Container Pricing can be deployed in the following three solution based scenarios:

  • Application Development and Test Solution: Add up to 3 times more capacity to existing Development and Test environments without any additional monthly licensing costs; or create new LPAR environments with competitive pricing.
  • New Application Solution: Add new z/OS microservices or applications, priced individually without impacting the cost of other workloads on the same system.
  • Payments Pricing Solution: A single agreed value based price for software plus hardware or just software, via a number of payments processed metric, based on IBM Financial Transaction Manager (FTM) software.

IBM state z14 support for a maximum 2 million Docker containers in an associated maximum 32 TB memory configuration.  In conjunction with other I/O enhancements, IBM state a z14 performance increase of ~300%, when compared with its z13 predecessor.  Historically the IBM Z platform was never envisaged as being the ideal container platform.  However, its ability to seamlessly support z/OS and Linux, while the majority of mission critical Systems Of Record (SOR) data resides on IBM Z platforms, might just be a compelling case for microservices to be processed on the IBM Z platform, minimizing any data latency transfer.

Container Pricing for z/OS is somewhat analogous to the IBM Cloud Managed Services on z Systems pricing model (I.E. CPU consumption based).  Therefore, if monthly R4HA peak processing is driven by an OLTP application, or any other workload for that matter, any additional unused capacity in that specific SCRT reporting month can be allocated for no cost to other workloads.  Therefore z/OS customers will be able to take advantage of this approach, processing collocated microservices or applications for a zero or nominal cost.

County Multiplex Pricing (CMP) Observation: The z14 is the first new generation of IBM Z hardware since the introduction of the CMP pricing mechanism.  When a client first implements a Multiplex, IBM Z server eligibility cannot be older than two generations (I.E. N-2) prior to the most recently available server (I.E. N).  Therefore the General Availability (GA) of z14, classifies the z114 and z196 servers as previously eligible CMP machines.  IBM will provide a 3 Month grace period for CMP transition activities for these N-3 servers, namely z114 and z196.  Quite simply, the first client CMP invoice must be submitted within 90 days of the z14 GA date, namely 13 September 2017, no later than 1 January 2018.

In conclusion, Pervasive Encryption is an omnipresent z14 function integrated into every data lifecycle stage, which could easily be classified as Persuasive Encryption, simplifying the sometimes arduous process of classifying and managing mission-critical data.  As cybersecurity becomes an omnipresent clear and present danger, associated with impending and increasingly punitive compliance mandates such as GDPR, the realm of possibility exists to resolve this high profile corporate challenge once and for all.

Likewise, Container Pricing provides a much needed simple-to-use framework to drive MSU cost optimization for new workloads and could easily be classified as Contained Pricing.  The committed IBM Mainframe customer will upgrade their z13 server environment to z14, as part of their periodic technology refresh approach.  Arguably, those Mainframe customers who have been somewhat hesitant in upgrading from older technology Mainframe servers, might just have a compelling reason to upgrade their environments to z14, safeguarding cybersecurity challenges and evolving processes to contain z/OS MLC costs.

Optimize Your System z ROI with z Operational Insights (zOI)

Hopefully all System z users are aware of the Monthly Licence Charge (MLC) pricing mechanisms, where a recurring charge applies each month.  This charge includes product usage rights and IBM product support.  If only it was that simple!  We then encounter the “Alphabet Soup” of acronyms, related to the various and arguably too numerous MLC pricing mechanism options.  Some might say that 13 is an unlucky number and in this case, a System z pricing specialist would need to know and understand each of the 13 pricing mechanisms in depth, safeguarding the lowest software pricing for their organization!  Perhaps we could apply the unlucky word to such a resource.  In alphabetical order, the 13 MLC pricing options are AWLC, AEWLC, CMLC, EWLC, MWLC, MzNALC, PSLC, SALC, S/390 Usage Pricing, ULC, WLC, zELC and zNALC!  These mechanisms are commercial considerations, but what about the technical perspective?

Of course, System z Mainframe CPU resource usage is measured in MSU metrics, where the usage of Sub-Capacity allows System z Mainframe users to submit SCRT reports, incorporating Monthly License Charges (MLC) and IPLA software maintenance, namely Subscription and Support (S&S).  We then must consider the Rolling 4-Hour Average (R4HA) and how best to optimize MSU accordingly.  At this juncture, we then need to consider how we measure the R4HA itself, in terms of performance tuning, so we can minimize the R4HA MSU usage, to optimize cost, without impacting Production if not overall system performance.

Finally, we then have to consider that WLC has a ~17-year longevity, having been announced in October 2000 and in that time IBM have also introduced hardware features to assist in MSU optimization.  These hardware features include zIIP, zAAP, IFL, while there are other influencing factors, such as HyperDispatch, WLM, Relative Nest Intensity (RNI), naming but a few!  The Alphabet Soup continues…

In summary, since the introduction of WLC in Q4 2000, the challenge for the System z user is significant.  They must collect the requisite instrumentation data, perform predictive modelling and fully comprehend the impact of the current 13 MLC pricing mechanisms and their interaction with the ever-evolving System z CPU chip!  In the absence of such a simple to use reporting capability from IBM, there are a plethora of 3rd party ISV solutions, which generally are overly complex and require numerous products, more often than not, from several ISV’s.  These software solutions process the instrumentation data, generating the requisite metrics that allows an informed decision making process.

Bottom Line: This is way too complex and are there any Green Shoots of an alternative option?  Are there any easy-to-use data analytics based options for reducing MSU usage and optimizing CPU resources, which can then be incorporated into any WLC/MLC pricing considerations?

In February 2016 IBM launched their z Operational Insights (zOI) offering, as a new open beta cloud-based service that analyses your System z monitoring data.  The zOI objective is to simplify the identification of System z inefficiencies, while identifying savings options with associated implementation recommendations. At this juncture, zOI still has a free edition available, but as of September 2016, it also has a full paid version with additional functionality.

Currently zOI is limited to the CICS subsystem, incorporating the following functions:

  • CICS Abend Analysis Report: Highlights the top 10 types of abend and the top 10 most abend transactions for your CICS workload from a frequency viewpoint. The resulting output classifies which CICS transactions might abend and as a consequence, waste processor time.  Of course, the System z Mainframe user will have to fix the underlying reason for the CICS abend!
  • CICS Java Offload Report: Highlights any transaction processing workload eligible for IBM z Systems Integrated Information Processor (zIIP) offload. The resulting output delivers three categories for consideration.  #1; % of existing workload that is eligible for offload, but ran on a General Purpose CP.  #2; % of workload being offloaded to zIIP.  #3; % of workload that cannot be transferred to a zIIP.
  • CICS Threadsafe Report: Highlights threadsafe eligible CICS transactions, calculating the switch count from the CICS Quasi Reentrant Task Control Block (QR TCB) per transaction and associated CPU cost. The resulting output identifies potential CPU savings by making programs threadsafe, with the associated CICS subsystem changes.
  • CICS Region CPU Constraint: Highlights CPU constrained regions. CPU constrained CICS regions have reduced performance, lower throughput and slower transaction response, impacting business performance (I.E. SLA, KPI).  From a high-level viewpoint, the resulting output classifies CICS Region performance to identify whether they’re LPAR or QR constrained, while suggesting possible remedial actions.

Clearly the potential of zOI is encouraging, being an easy-to-use solution that analyses instrumentation data, classifies the best options from a quick win basis, while providing recommendations for implementation.  Having been a recent user of this new technology myself, I would encourage each and every System z Mainframe user to try this no risk IBM z Operational Insights (zOI) software offering.

The evolution for all System z performance analysis software solutions is to build on the comprehensive analysis solutions that have evolved in the last ~20+ years, while incorporating intelligent analytics, to classify data in terms of “Biggest Impact”, identifying “Potential Savings”, evolving MIPS measurement, to BIPS (Biggest Impact Potential Savings) improvements!

IBM have also introduced a framework of IT Operations Analytics Solutions for z Systems.  This suite of interconnected products includes zOI, IBM Operations Analytics for z Systems, IBM Common Data Provider for z/OS and IBM Advanced Workload Analysis Reporter (IBM zAware).  Of course, if we lived in a perfect world, without a ~20 year MLC and WLC longevity, this might be the foundation for all of our System z CPU resource usage analysis.  Clearly this is not the case for the majority of System z Mainframe customers, but zOI does offer something different, with zero impact, both from a system impact and existing software interoperability viewpoint.

Bottom Line: Optimize Your System z ROI via zOI, Evolving From MIPS Measurement to BIPS Improvements!

Are You Ready For z Systems Workload Pricing for Cloud (zWPC) for z/OS?

Recently IBM announced the z Systems Workload Pricing for Cloud (zWPC) for z/OS pricing mechanism, which can minimize the impact of new Public Cloud workload transactions on Sub-Capacity license charges.  Such benefits will be delivered where higher Public Cloud workload transaction volumes may cause a spike in machine utilization.  Of course, if this looks familiar and you have that feeling of déjà vu, this is a very similar mechanism to Mobile Workload Pricing (MWP)…

Put simply, zWPC applies to any organization that has implemented Sub-Capacity pricing via the basic AWLC or AEWLC pricing mechanisms, for the usual MLC software suspects, namely z/OS, CICS, DB2, IMS, MQ and WebSphere Application Server (WAS).  An eligible transaction is one classified as Public Cloud originated, connecting to a z/OS hosted transactional service and/or data source via a REST or SOAP web service.  Public Cloud workloads are defined as transactions processed by named Public Cloud applications transactions identified as originating from a recognized Public Cloud offering, including but not limited to, Amazon Web Services (AWS), Microsoft Azure, IBM Bluemix, et al.

As per MWP, SCRT calculates the R4HA for Public Cloud transaction GP MSU resource usage, subtracting 60% of those values from the traditional Sub-Capacity software eligible MSU metric, with LPAR granularity, for each and every reporting hour.  The software program values for the same hour are aggregated for all Sub-Capacity eligible LPARs, deriving an adjusted Sub-Capacity value for each reporting hour.  Therefore SCRT determines the billable MSU peak for a given MLC software program on a CPC using the adjusted MSU values.  As per MWP, this will only be of benefit, if the Public Cloud originated transactions generate a spike in the current R4HA.

One of the major challenges for implementing MWP was identifying those transactions eligible for consideration.  Very quickly IBM identified this challenge and offered a WorkLoad Manager (WLM) based solution, to simplify reporting for all concerned.  This WLM SPE (OA47042), introduced a new transaction level attribute in WLM classification, allowing for identification of mobile transactions and associated processor consumption.  These Reporting Attributes were classified as NONE, MOBILE, CATEGORYA and CATEGORYB.  Obviously IBM made allowances for future workload classifications, hence it would seem Public Cloud will supplement Mobile transactions.

In a previous z/OS Workload Manager (WLM): Balancing Cost & Performance blog post, we considered the merits of WLM for optimizing z/OS software costs, while maintaining optimal performance.  One must draw one’s own conclusions, but there seemed to be a strong case for WLM reporting to be included in the z/OS MLC Cost Manager toolkit.  The introduction of zWPC, being analogous to MWP, where reporting can be simplified with supplied and supported WLM function, indicates that intelligent and proactive WLM reporting makes sense.  Certainly for 3rd party Soft-Capping solutions, the ability to identify MWP and zWPC eligible transactions in real-time, proactively implementing MSU optimization activities seems mandatory.

The Workload X-Ray (WLXR) solution from zIT Consulting delivers this WLM reporting function, seamlessly integrating with their zDynaCap and zPrice Manager MSU optimization solutions.  Of course, there is always the possibility to create your own bespoke reports to extract the relevant information from SMF records and subsystem diagnostic data, for input to the SCRT process.  However, such a home-grown process will only work on a monthly reporting basis and not integrate with any Soft-Capping MSU management, which will ultimately control z/OS MLC costs.

In conclusion, from a big picture viewpoint, in the last 2 years or so, IBM have introduced several new Sub-Capacity pricing mechanisms to help System z Mainframe users optimize z/OS MLC costs, namely Mobile Workload Pricing (MWP), Country Multiplex Pricing (CMP) and now z Systems Workload Pricing for Cloud (zWPC).  In theory, at least one of these new pricing mechanisms should deliver benefit to the committed System z user, deploying this server for strategic and Mission Critical workloads.  With the undoubted strategic importance associated with Analytics, Blockchain, Cloud, DevOps, Mobile, Social, et al, the landscape for System z workloads is rapidly evolving and potentially impacting those sacrosanct legacy Mission Critical workloads.  Seemingly the realm of possibility exists that Cloud and Mobile originated transactions will dominate access to System z Mainframe System Of Record (SOR) data repositories, which generates a requirement to optimize associated MLC costs accordingly.  Of course, for some System z users, such Cloud and Mobile access might not be on today’s to-do list, but inevitably it’s on the horizon, and so why not implement the instrumentation ability ASAP!

z13 WLC Software Pricing Updates: Are You Ready?

Along with the z13 hardware announcement were several very obvious WLC pricing announcements, but more importantly, two hidden Statements Of Direction (SOD) or pre-announcements.

I guess we can all remember the “zSeries Technology Dividend” where put simply, when upgrading zSeries servers, users would benefit from a ~10%+ software price versus performance benefit.  Does anybody still remember the IBM Mainframe Charter from 2003?  That was the document that first referenced this price/performance benefit, which became known as the “technology dividend”.  Specifically, this document stated:

IBM lowered MSU values incorporated in the z990 microcode by approximately 10 percent, resulting in IBM software savings for IBM zSeries software products with MSU-based pricing.  These reduced MSUs do not indicate a change in machine performance. Superior performance and technology within the z990 has allowed IBM to provide improved software prices for key IBM zSeries operating system and middleware software products.

Put really simply, for z990, z9 and z10 server upgrades, IBM delivered this ~10% benefit with faster CPU chips.  Therefore, no noticeable impact on Software Pricing, Capacity Planning or Performance Measurement processes.  However, with the z196/z114, this ~10% benefit could no longer be delivered by CPU chip hardware speed enhancements.  To compensate, IBM introduced the Advanced Workload License Charges (AWLC) pricing regime.  AWLC is an evolution of the Variable (VWLC) pricing regime, lowering per MSU costs for WLC eligible products (E.g. z/OS, CICS, DB2, IMS, WebSphere/MQ, et al).  Hence delivering the ~10% price/performance benefit when upgrading from a z10 to a z196 or z114 (AEWLC) server.

Of course, when upgrading to the zEC12 or zBC12, further refinement of AWLC pricing was required, to deliver this the ~10% price/performance benefit.  Hence, IBM introduced the AWLC Technology Transition Offerings (TTO), lowering AWLC prices for zXC12 and now z13 zSeries servers.

For z13, IBM announced the following z13 AWLC Technology Transition Offerings:

  • Technology Update Pricing for the IBM z13 (TU3): When stand-alone z13 servers are priced with AWLC, or when all the servers in an aggregated Sysplex or Complex are z13 servers priced with AWLC, these servers receive a reduction to AWLC pricing which is called.  Quantity of z13 Full Capacity MSUs for a stand-alone server, or the sum of Full Capacity MSUs in an actively coupled Parallel Sysplex or Loosely Coupled Complex made up entirely of z13 servers.  AWLC discounts range from 4% (4-45 MSU) to 14% (5477+ MSU).
  • AWLC Sysplex Transition Charges (TC2): When two or more machines exist in an aggregated Sysplex or Complex & at z13, zEC12, or zBC12 server & at least one is a z196 or z114 server, with no older technology machines included, they will receive a reduction to AWLC pricing across the aggregated Sysplex or Complex. This reduction provides a portion of the benefit related to the Technology Update Pricing for AWLC (TU1) based upon the proportion of zEC12 or zBC12 server capacity in the Sysplex or Complex.  AWLC discounts range from 0.5% (0-20% z13/zXC12 MSU) to 4.5% (81%-<100% z13/zXC12 MSU).
  • AWLC Sysplex Transition Charges (TC3): When two or more machines exist in an aggregated Sysplex or Complex & at least one is a z13 server & at least one is a zEC12 or zBC12 server, with no older technology machines included, they will receive a reduction to AWLC pricing across the aggregated Sysplex or Complex. This reduction provides a portion of the benefit related to the IBM z13 TU3 offering, based on the total Full Capacity MSU of all z13, zEC12, & zBC12 Machines in the Sysplex or Complex.  AWLC discounts range from 2.8% (4-45 MSU) to 9.8% (5477+ MSU).

These AWLC software pricing announcements are Business As Usual (BAU) and to be expected, but if we dig slightly deeper into the z13 announcements, we will find two other pre-announcements of interest!

Since introducing sub-capacity and WLC pricing regimes, IBM have continually evolved zSeries software sub-capacity pricing mechanisms, with zNALC, AWLC, IWP and more recently MWP offerings.  From a generic viewpoint, with the exception of zNALC, a niche new workload price offering, these pricing announcements did not challenge the “status quo”, where aggregated MSU and large LPAR structures were the ideal.  So why might the upcoming z13 (E.g. Q2 2015) pricing announcements be of note?  Primarily because they challenge the notion of having separate structural entities (I.E. Sysplex Coupled zSeries Servers & LPARS) for existing and new workloads.

Country Multiplex Pricing (CMP): A major evolution, essentially eliminating prior Sysplex pricing rules, requiring that systems be interconnected and/or sharing the same data in order to be eligible for aggregation of MLC software pricing charges.  A Multiplex is defined as the collection of all z Systems within a country.  Therefore, sub-capacity usage will be measured & reported as a single machine, regardless of the connectivity or data sharing configurations.  A new sub-capacity reporting tool is being implemented & clients should expect a transition period as the new pricing model is implemented.  This should allow flexibility to move & run work anywhere, eradicating multiple workload peaks when workloads move between machines.  Ultimately the cost of growth is reduced with one price per product based on MLC capacity growth anywhere in the country.CMP should facilitate for flexible deployment and movement of business workloads between all zSeries Servers located within a country, without impacting MLC billing.  For the avoidance of doubt, this will assist the customer in safeguarding they don’t encounter duplicate MLC peaks as a result of moving an LPAR workload from one zSeries Server to another.  It also removes all Sysplex aggregation considerations, Single Version Charging (SVC) time limits and Cross Systems Waivers (CSW).  Most notably, the cost per MSU for additional capacity will be optimized, being based upon total Multiplex MSU capacity.

IBM Collocated Application Pricing (ICAP): Previously, new applications (zNALC) required a separate LPAR to avoid increases in other MLC software charges.  ICAP facilitates new eligible applications be charged as if they are running in a dedicated environment.  Technically they are integrated with other (non-eligible) workloads.  Software supporting the new application will not impact the charges for other MLC software collocated in the same LPAR.  ICAP appears as an evolution of the Mobile Workload Pricing (MWP) for z/OS pricing mechanism.  ICAP will use an enhanced MWRT, implemented as a z/OS application.  ICAP applies to z13, zXC12, z196/z114 servers.  IBM anticipates that ICAP will deliver zNALC type price benefit, discounting ~50% of ICAP eligible software MSU.

Seemingly IBM have learned from the lessons of IWP, where at first glance, software discounts were attractive, but not at the cost of a separate LPAR.  From a reporting viewpoint, there are similarities to Mobile Workload Pricing for z/OS (MWP), but most notably, pricing is largely zNALC based.  Therefore collocating new workloads in the same LPAR as existing workloads, but with the best price performance of any pricing regime, except zNALC, which is a niche and special edition software pricing metric.

In conclusion, CMP and ICAP are notable WLC pricing regime updates, because they do challenge the status quo of MSU aggregation via Sysplex coupled servers and the ability to collocate new and existing workloads in the same LPAR.  On the one hand, simplified pricing considerations from a granular per MSU cost viewpoint.  However, to optimize price versus performance, arguably the savvy Data Centre will now require a higher level of workload management, safeguarding optimum MSU capacity usage and associated performance.

zPrice Manager is an evolution of the typical soft-capping approach, which can be IBM function based, namely Defined Capacity (DC) or Group Capacity Limit (GCL), or ISV product based.  ISV products typically allow MSU management with dynamic MSU capacity resource management between LPAR, LPAR Group & CPC structures, ideally with Workload Manager (WLM) interaction.  If plug & play simple MSU management is required, these traditional IBM or 3rd party ISV approaches will still work with CMP and ICAP, but will they maximize WLC TCO?

The simple answer is no, because CMP allows the movement of workloads between zSeries Servers.  Therefore if WLC product (I.E. z/OS, CICS, DB2, IMS, WebSphere/MQ) pricing is to be country wide, and optimum WLM performance is to be maintained, a low level granularity of MSU management is required.

zPrice Manager from zIT Consulting allows this level of WLC software product management, with a High Level REXX programmatic interface, and the ability to store real life MSU profile data as callable REXX variables.  Similar benefits apply to ICAP workloads, where different WLM policies might be required for the same WLC product, deployed on the same collocated workload LPAR.  Therefore the savvy data centre will safeguard they optimize MSU TCO via MWP and/or ICAP pricing regimes, without impacting business application performance.

In conclusion, the typical z13 AWLC software pricing updates are Business As Usual (BAU) and can be implemented, as and when required and without consideration.  Conversely, CMP and ICAP can deliver significant future benefit and should be considered in zSeries Server capacity planning forecasts.

Bottom Line Recommendation: Each and every zSeries Server user, whether large or small, should initiate contact with their IBM account teams, for CMP and ICAP briefings, allowing them to consider how they might benefit from these new WLC software pricing regimes.

Are You Ready For z/OS Mobile Workload Pricing (MWP)?

Recently IBM announced Mobile Workload Pricing (MWP) for z/OS which can minimize the impact of mobile workloads on Sub-Capacity license charges, delivering optimized pricing for System z environments extending their workloads to incorporate mobile devices.

MWP only applies to Mainframe customers deploying a zEC12 or zBC12 in their enterprise, as per the AWLC or AEWLC (AKA Advanced/Entry Workload License Charges) metric; MWP is also extended if a zEC12 or zBC12 enterprise is deploying a z196 or z114 via the AWLC or AEWLC metric.

The primary consideration for MWP is determining how a Mainframe customer can comply with the tracking requirements for mobile workloads.  On the plus side, MWP does not require an isolation of mobile workload transactions in separate LPARs, using enhanced reporting for software pricing.  This is a major step forward when compared with Integrated Workload Pricing (IWP), which ideally requires large LPAR container structures, minimizing costs for WebSphere workloads, applying to the CICS, IMS and WebSphere MLC software products.  Conversely, MWP includes DB2 in the list of eligible software products for cost reduction.

If a Mainframe customer is eligible for MWP pricing they will then need to utilize the Mobile Workload Reporting Tool (MWRT), which is analogous to the original Sub-Capacity Reporting Tool (SCRT).  This is an either/or situation, the Mainframe customer only submits MCRT reports to IBM if they’re MWP eligible, or the status quo remains, where non-MWP Mainframe customers continue to submit SCRT reports.

The Mainframe customer must track and report General Purpose (GP) CPU time for mobile transactions, reporting those values in a pre-defined format to IBM each month to benefit from MWP.  MWRT utilizes reported mobile transaction data to adjust the Rolling 4 Hour Average (R4HA) Sub-Capacity software eligible MSUs, with LPAR granularity.  Optimizing mobile transactions impact for peak LPAR MSU values delivers benefit when higher mobile transaction volumes generate MSU resource usage peaks (Workload Spikes).

MWRT calculates the R4HA for mobile transaction GP MSU resource usage, subtracting 60% of those values from the traditional Sub-Capacity software eligible MSU metric, with LPAR granularity, for each and every reporting hour.  The software program values for the same hour are aggregated for all Sub-Capacity eligible LPARs, deriving an adjusted Sub-Capacity value for each reporting hour.  Therefore MWRT determines the billable MSU peak for a given MLC software program on a CPC using the adjusted MSU values.

Most committed zSeries Mainframe customers will be deploying CICS, DB2 and WebSphere software, while IT trends dictate that mobile device usage (I.E. Smartphone, Tablet, et al) is increasing.  Therefore most z/OS applications that require such mobile access have evolved accordingly over time.  Therefore it seems to be one of those “No Brainer” type scenarios, where the Mainframe user should plan to benefit from MWP, either as they upgrade to the latest zSeries technology, namely zEC12 or zBC12, or immediately if already deploying a zEC12 or zBC12 server.

The only minor consideration is a requirement for the zEC12 or zBC12 customer to engage their local IBM account team, to determine what data they need to report on mobile transactions for MWP consideration.  This one off task will deliver optimized WLC pricing forever more.

Of course IBM are encouraging customers to consider the Mainframe for new applications, driven by mobile transaction requirements.  Equally, there is no reason why longer term Mainframe customers can’t benefit from MWP, benefitting from reduced MLC costs, a major consideration of Mainframe TCO.

z/OS Soft Capping: Balancing Cost & Performance

Historically each and every LPAR was assigned a Relative Weight value; where a more meaningful description would be the initial processing weight. This relative weight value is used to determine which LPAR gains access to resources, where multiple LPARs are competing for the same resource. Being unit-less is one minor challenge of the relative weight value, meaning that it has no explicit CPU capacity or resource value. Typically installations would use a simple multiple of ten metric, most likely 1000, and allocate weights accordingly (E.g. 600=60%, 300=30%, 10=10%, et al). Therefore during periods of resource contention, PR/SM would allocate resources to the requisite LPAR, based upon its relative weight.

Using relative weight to classify all LPARs as equal, at least from a generic class viewpoint, does have some considerations; primarily differentiating between Production and Non-Production workloads. Restricting a workload to its relative weight share of resources is known as Hard Capping. This setting is typically used to restrict Non-Production (E.g. Test) environments to their allocated resource and is also useful for cost control (E.g. Outsourcers), knowing that the LPAR will never consume more than its allocated relative weight allowance.

Hard Capping behaviour changes dependent on the use of the HiperDispatch setting. When HiperDispatch is not chosen, capping is performed at the Logical CP level, where the goal is for each logical CP to receive its relative CP share, based on the relative weight setting. When HiperDispatch is active, vertical as opposed to horizontal CPU management applies. So, a High categorization dictates capping at 100% of the logical CP, whereas a Medium or Low setting allows for resource sharing based on a relative weight per CP basis.

The Intelligent Resource Director (IRD) function provides more advanced relative weight management, automating management of CPU resources and a subset of I/O resources. Workload Manager (WLM) manages physical CPU resource across z/OS images within an LPAR cluster based on service class goals. IRD is implemented as a collaboration between the WLM function and the PR/SM Logical Partitioning (LPAR) hypervisor:

  • Logical CP Management: dynamically allocating logical processors (E.g. Vary On-Line/Off-Line)
  • Relative Weight Management: dynamically redistributing CPU resource as per LPAR weights
  • CHPID Management: dynamically assigning logical channel paths between eligible LPARs

IRD optimizes resource usage, enabling WLM to deliver workload goals.

The use of relative weight in association with Hard Capping and/or IRD/WLM granularity has become somewhat limited for most Mainframe installations with the advent of Sub-Capacity pricing (I.E. MLC via SCRT/R4HA). Primarily because there is no direct correlation to manage CPU resource at a meaningful level, namely the MSU (vis-à-vis CPU MIPS) metric.

Defined Capacity (DC) provides Sub-Capacity CEC pricing by allowing definition of LPAR capacity with a granularity of 1 MSU. In conjunction with the WLM function, the Defined Capacity of an LPAR dictates whether Soft Capping is invoked or not. At this juncture, we should consider how and when WLM measures CPU resource usage and if and when Soft Capping is activated and deactivated:

WLM is responsible for taking MSU utilization samples for each LPAR in 10-second intervals. Every 5 minutes, WLM documents the highest observed MSU sample value from the 10-second interval samples. This process always keeps track of the past 48 updates taken for each LPAR. When the 49th reading is taken, the 1st reading is deleted, and so on. These 48 values continually represent a total of 5 minutes * 48 readings = 240 minutes or the past 4 hours (I.E. R4HA). WLM stores the average of these 48 values in the WLM control block RCT.RCTLACS. Each time RMF (or BMC CMF equivalent) creates a Type 70 record, the SMF70LAC field represents the average of all 48 MSU values for the respective LPAR a particular Type 70 record represents. Hence, we have the “Rolling 4 Hour Average”. RMF gets the value populated in SMF70LAC from RCT.RCTLACS at the time the record is created.

SCRT also uses the Type 70 field SMF70WLA to ensure that the values recorded in SMF70LAC do not exceed the maximum available MSU capacity assigned to an LPAR. If this ever happens (due to Soft Capping or otherwise) SCRT uses the value in SMF70WLA instead of SMF70LAC. Values in SMF70WLA represent the total capacity available to the LPAR.

We should also consider the two possibilities for MLC software payment (I.E. SCRT) based upon MSU resource usage. Quite simply, the MSU value passed for SCRT invoice consideration is the R4HA or the Defined Capacity, whichever is the lowest. Put another way; if the R4HA exceeds Defined Capacity, Soft Capping applies to the LPAR.

The primary disadvantage of Soft Capping is that the Defined Capacity setting is somewhat static; it is manually defined once, maybe several times a day for workloads with distinct characteristics (E.g. On-Line, Batch, et al), but dynamic DC management based upon inter-related LPAR behaviour is at best, evolving. The primary considerations for Soft Capping are:

  • An LPAR can only be managed via Soft Capping or Hard Capping; not both
  • DC rules only applies to General Purpose CP’s (Hard Capping for Specialty Engines is allowed)
  • An LPAR must be defined with shared CP’s (dedicated CP’s not allowed)
  • All LPAR Sub-Capacity eligible products have the same MSU capacity (I.E. DC)

Soft Capping is relatively simple to implement and typically generates MLC software costs savings, with minimal impact.

Group Capacity Limit (GCL) provides an extension to the Defined Capacity (DC) Soft Capping function. GCL allows an MSU limit for total usage of all group LPARs, with a granularity of 1 MSU. The primary considerations for GCL are:

  • Works with DC LPAR capacity settings
  • Target share does not exceed DC
  • Works with IRD
  • Multiple CEC groups allowed; but an LPAR may only be defined to one group
    An LPAR must be defined with shared CP’s, with WAIT COMPLETION = NO specification

It is possible to combine IRD weight management with the GCL function. Based on installation policy, IRD can modify the relative weight setting to redistribute capacity resource within an LPAR cluster.

However, IRD weight management is suspended when GCL is in effect, because LPAR resource entitlement within a capacity group can be (I.E. Pre zxC12) derived from the current weight. Hence the LPAR might get allocated an unacceptable low weight setting, generating a low GCL entitlement.

GCL also allows for MSU to be shared between LPARs in a group, where one LPAR would be a donator and another would be a receiver. Therefore the customer classifies their LPARs accordingly and when a high-priority LPAR requires additional MSU resource, it will be allocated from a lower priority LPAR, if available. This provides a modicum of flexibility, but by definition, peak workloads are not predictable and typically require a significantly higher amount of MSU for a short time period. Typically this requirement will not be satisfied with the GCL function.

Soft Capping techniques, either at the individual (DC) or group (GCL) level deliver cost saving benefit, but a fine granularity of management is required to balance cost saving versus associated performance considerations. The primary challenges associated with Soft Capping are its interactions with workload characteristics and an inability to dynamically manage MSU allocation, in-line with the R4HA. Put another way, the R4HA is derived from 48*5 Minute samples, whereas DC and GCL settings are typically defined on an infrequent (E.g. Monthly or longer) basis.

As z/OS evolves, further in-built function is available to manage MSU capacity. zSeries Capacity Provisioning Manager (CPM) is designed to simplify the management of temporary capacity, defined capacity and group capacity. The scope of z/OS Capacity Provisioning is to address capacity requirements for relatively short term workload fluctuations for which On/Off Capacity on Demand or Soft Capping changes are applicable. CPM is not a replacement for the customer derived Capacity Management process. Capacity Provisioning should not be used for providing additional capacity to systems that have Hard Capping (initial capping or absolute capping) defined.

With the introduction of z/OS 2.1, CPM functionality incorporates Soft Capping support via the DC and GCL functions. CPM functions from a set of installation defined policies and parameters, where the CPM server receives three types of input:

  • Domain Configuration: defines the CPCs and z/OS systems to be managed
  • Policy: contains the information as to which work is eligible, for which conditions and during which timeframes and capacity increases for constrained workloads
  • Parameter: contains environment descriptors (E.g. UNIX Environment, Installation Options, et al)

From a customer viewpoint, policy definition allows them to define the provision of CPU resource:

  • Date & Time: When capacity provisioning is allowed
  • Workload: Which service class qualifies for provisioning?
  • CPU Resource: How much additional MSU capacity can be allocated?

CPM provides more function when compared with Defined Capacity and Group Capacity Limit Soft Capping techniques. Therefore allowing for time schedules to be defined, workloads to be categorized and MSU resource to be allocated in a dynamic and granular manner.

A modicum of complexity exists when considering the arguably most important factor for CPM policy definition, namely the Performance Index (PI):

  • Activation: PI of service class periods must exceed the activation threshold for a specified duration, before the work is considered as eligible.
  • Deactivation: PI of service class periods must fall below the deactivation threshold for a specified duration, before the work is considered as ineligible.
  • Null: If no workload condition is specified a scheduled activation/deactivation is performed; with full capacity as specified in the rule scope, unconditionally at the start and end times of the time condition.

For workload based provisioning it is a necessary condition that the current system Performance Index exceeds the specified customer policy PI metric. One must draw one’s own conclusions regarding PI criteria settings, but to date, they’re largely based on arguably complex mathematical formulae, which perhaps is not practicable, especially from a simple management viewpoint.

With the requisite hardware (I.E. zxC12+) and Operating System levels (I.E. z/OS 1.13+), CPM provides extra functionality for the customer to implement granular Soft Capping techniques to balance cost and performance. When compared with Defined Capacity and Group Capacity Limit techniques, CPM delivers increased granularity for managing capacity dynamically, based on customer derived policies, recognizing time slots, workloads and MSU resource increases accordingly.

From a big picture viewpoint, without doubt, we must recognize the fundamental role that WLM plays in Soft Capping. Quite simply, the 48*5 Minute MSU resource samples dictate whether a workload will be eligible for Soft Capping or not and from a cumulative viewpoint, these MSU samples dictate the R4HA metric. Based on this observation, efficient and functional Soft Capping must be workload based (I.E. WLM Service Class), be dynamic and operational on a 24*7 basis, because workload peaks are never predictable, while balancing MSU resource accordingly. Of course, simplicity of implementation and management, supplemented by meaningful reporting is mandatory.

Once again, observing the 48*5 Minute MSU resource samples from a R4HA viewpoint, if a workload was to increase MSU usage by an average of 50% for 1 Hour (I.E. 12 Samples), and decrease MSU usage by an average of 20% for 2.5 Hours (I.E. 30 Samples), from an average viewpoint, the R4HA has remained static. Therefore an optimum Soft Capping technique needs to recognize WLM service class requirements, reacting in a timely manner, increasing and decreasing MSU usage, to safeguard workload performance for Time Critical workloads, while optimizing SCRT MLC cost.

zDynaCap delivers automated capacity balancing within CPCs, Capacity Groups or Groups of LPARs. Central to zDynaCap are the predefined balancing policies. Within these balancing policies, users define their MSU ranges of Groups and LPARs and also the priorities of the associated LPAR Workload. zDynaCap continually monitors overall usage and compares this to the available capacity and the user defined MSU balancing policies. For example, should a high priority workload on one LPAR not get enough capacity, while a low priority workload on another within the group gets too much capacity, available MSU capacity is distributed according to customer derived balancing policies. Only if there is no leftover capacity to be rescheduled within the defined Group, and if the high or medium priority workload will be slowed down, will zDynaCap add MSU.

With zDynaCap Capacity Balancing, available MSU capacity is balanced within LPAR groups, safeguarding that during peak time the mission critical workload is processed as per business expectations (E.g. SLA/KPI) for the lowest possible MLC cost.

In conclusion, given the significance of IBM MLC software (E.g. z/OS, CICS, DB2, IMS, WebSphere MQ, et al) costs, arguably every Mainframe environment should deploy a capping technique for cost optimization. Hard Capping might work for some, but in all likelihood, Soft Capping is the primary choice for most Mainframe environments. For sure, IBM have delivered several Soft Capping techniques, with varying levels of function and granularity, namely Defined Capacity, Group Capacity Limit (GCL) and the zSeries Capacity Provisioning Manager (CPM). It was forever thus and the ISV community exists because they specialize, architect and deliver specialized solutions and zDynaCap is such a solution, recognizing the fundamental rules of IBM Mainframe Soft Capping, namely the underlying WLM and R4HA foundation.

IBM Mainframe: Workload License Charges (WLC) Pros & Cons

It is estimated that less than half of eligible IBM Mainframe customers deploy the VWLC pricing mechanism, which in theory, is the lowest cost IBM software pricing metric.  Why?  In the first instance, let’s review the terminology…

Workload License Charges (WLC) is a monthly software license pricing metric applicable to IBM System z servers running z/OS or z/TPF in z/Architecture (64-bit) mode.  The fundamental ethos of WLC is a “pay for what you use” mechanism, allowing a lower cost of incremental growth and the potential to manage software cost by managing associated workload utilization.

WLC charges are either VWLC (Variable) or FWLC (Flat).  Not all IBM Mainframe software products are classified as VWLC eligible, but the major software is, including z/OS, CICS, DB2, IMS and WebSphere MQ, where these products are the most expensive, per MSU.  What IBM consider to be legacy products, are classified as FWLC.  More recently a modification to the VWLC mechanism was announced, namely AWLC (Advanced), strictly aligned with the latest generation of zSeries servers, namely zEC12, z196 and z114.  For the smaller user, the EWLC (Entry) mechanism applies, where AEWLC would apply for the z114 server.  There is a granular cost structure based on MSU (CPU) capacity that applies to VWLC and associated pricing mechanisms:

Band MSU Range
Base 0-3 MSU
Level 0 4-45 MSU
Level 1 46-175 MSU
Level 2 176-315 MSU
Level 3 316-575 MSU
Level 4 576-875 MSU
Level 5 876-1315 MSU
Level 6 1316-1975 MSU
Level 7 1976+ MSU

Put simply, as the MSU band increases, the related cost per MSU decreases.

IBM Mainframe users can further implement cost control by specifying how much MSU resource they use by deploying Sub-Capacity and Soft Capping techniques.  Defined Capacity (DC) allows the sizing of an LPAR in MSU, and so said LPAR will not exceed this MSU amount.  Group Capacity Limit (GCL) extends the Defined Capacity principle for a single LPAR to a group of LPARs, and so allowing MSU resource to be shared accordingly.  A potential downside of GCL is that is one LPAR of the group can consume all available MSU due to a rogue transaction (E.g. loop).

Sub-Capacity software charges are based upon LPAR hardware utilization, where the product runs, measured in hourly intervals.  To smooth out isolated usage peaks, a Rolling 4-Hour Average (R4HA) is calculated for each LPAR combination, and so software charges are based on the Monthly R4HA peak of appropriate LPAR combinations (I.E. where the software product runs) and not based on individual product measurement.

Once a Defined Capacity LPAR is deployed, this informs WLM (Workload Manager) to monitor the R4HA utilization of that LPAR.  If the LPAR R4HA utilization is less than the Defined Capacity, nothing happens.  If the LPAR R4HA utilization exceeds the Defined Capacity, then WLM signals to PR/SM and requests that Soft Capping be initiated, constraining the LPAR workload to the Defined Capacity level.

If a user chooses a Sub-Capacity WLC pricing mechanism, they will be required by IBM to submit a monthly Sub-Capacity Reporting Tool (SCRT) report.  Monthly WLC invoices are based upon hourly utilization metrics of LPAR hardware utilization, where the software product executes.  The cumulative R4HA and bottom line WLC billing metric is calculated for each product and associated LPAR group and not based on individual product measurement.

Bottom Line: From a Soft Capping viewpoint, the customer only pays for WLC software based upon the Defined Capacity (DC) or Rolling 4-Hour Average (R4HA), whichever is the lowest.  So whether a customer uses Soft Capping or not, in all likelihood, there will be occasions when their workload R4HA is lower than their zSeries server MSU capacity.

So, at first glance, VWLC seems to provide a compelling pricing metric, based upon Sub-Capacity and a pay for what you use ethos, and so why wouldn’t an IBM Mainframe user deploy this pricing metric?

The IBM Planning for Sub-Capacity Pricing (SA22-7999-0n) manual states “For IBM System z10 BC and System z9 BC environments, and z890 servers, EWLC pricing is the default for z/OS systems, and Sub-Capacity pricing is always the best option.  For IBM zEnterprise 114, environments, AEWLC pricing is the default for z/OS systems, and Sub-Capacity pricing is always the best option.  For IBM zEnterprise 196, System z10 EC and System z9 EC environments, and other zSeries servers, Sub-Capacity pricing is cost-effective for many, but not all, customers.  You might even find that Sub-Capacity pricing is cost effective for some of your CPCs, but not others (although if you want pricing aggregation, you must always use the same pricing for all the CPCs in the same sysplex)”.

Conclusion: For all small Mainframe users qualifying for the EWLC (AEWLC) pricing metric, arguably this pricing mechanism is mandatory.  For the majority of larger Mainframe users, the same applies, although a granularity of adoption might be required.  IBM also have a disclaimer “Once you decide to use Sub-Capacity pricing for a specific operating system family, you cannot return to the alternative pricing methods for that operating system family on that CPC.  For example, once you select WLC you may not switch back to PSLC without prior IBM approval”.  However, the requisite contractual exit clause option does exist; the customer can switch back to the PSLC pricing metric.

Some IBM Mainframe users might object to a notion of Soft Capping, relying upon their tried and tested methodology of LPAR management via the number of CPs allocated and associated PR/SM Weight.  This is seemingly a valid notion and requirement, prioritizing performance ahead of cost optimization.

Conclusion: As previously indicated, with VWLC, SCRT invoices are generated upon a premise of the customer only pays for WLC software based upon the Defined Capacity (DC) or Rolling 4-Hour Average (R4HA), whichever is the lowest.  So the VWLC pricing mechanism should deliver a granularity of cost savings, typically higher for a Soft Capping environment.

Some IBM Mainframe users might just believe that nothing can match their Parallel Sysplex Licensing Charge (PSLC) mechanism, first available in the late 1990’s, which might be attributable to other 3rd party ISV’s who cannot and will not allow for their software to be priced on a Sub-Capacity basis.  In reality, adopting the VWLC pricing mechanism delivers ~5% cost savings when compared with PSLC, as indicated by the IBM Planning for Sub-Capacity Pricing Manual (SA22-7999-0n) and related Sub-Capacity Planning Tool (SCPT).

Conclusion: Adopting Sub-Capacity based pricing metrics can only be a good thing.  If your 3rd party ISV supplier doesn’t recognise Sub-Capacity pricing, whether MIPS or MSU based, perhaps you should consider your relationship with them.  Regardless, the z10 server was the last IBM Mainframe to incorporate the “Technology Dividend” solely based on faster CPU chips.  The lower cost WLC pricing metric is now only available with the AWLC and related (E.g. AEWLC) pricing metrics, as per the z196, z114 and zEC12 servers.

Some customers might state that there is a lack of function or granularity of policy definition for IBM supplied Soft Capping (E.g. DC, GCL) or Workload Management (WLM) techniques.  To some extent this is a valid argument, but wasn’t it forever thus with IBM function?  Sub-Capacity implementation is possible via IBM, as is Workload Management (WLM), Soft Capping or not, but should the customer require extra functionality, 3rd party software solutions are available.

The zDynaCap software solution from zIT Consulting delivers a “Capacity Balancing” mechanism, integrating with R4HA and WLM methodologies, but constantly monitoring MSU usage to determine whether CPU resource can be reallocated to Mission & Time Critical workloads, based upon granular customer policies.  The only guarantee in a multiple LPAR environment, for a Mission & Time Critical LPAR to receive all available MSU resource, Soft Capping or not, is to inactivate all other LPARs!  Clearly this is not an acceptable policy for any installation, and so a best endeavours policy applies for PR/SM DC, GCL and Weight settings.

Conclusion: z/OS workloads change constantly, whether the time of day (E.g. On-Line, Batch) or period of the year (E.g. Weekly, Monthly, Quarterly, Yearly) or just by customer demand (E.g. 24 Hour Transaction Application).  Therefore a dynamic MSU management solution such as zDynaCap is arguably mandatory, implementing the optimum MSU management policy, whether for purely performance reasons, safeguarding the Mission & Time Critical workload isn’t impacted by lower priority workloads, or for cost reasons, optimizing MSU usage for the best possible monthly WLC cost.

In conclusion, not considering and arguably not implementing z/OS VWLC related pricing mechanisms is impractical, because:

  • The VWLC and AWLC related pricing metrics deliver the lowest cost per MSU for eligible z/OS software
  • When compared with PSLC, VWLC related pricing mechanisms deliver conservative ~5% cost savings
  • A pay for what you use and therefore Sub-Capacity pricing mechanism, not the installed MSU capacity
  • If extra MSU policy management granularity is required, consider 3rd party software such as zDynaCap

Software cost savings are not just for the privileged; they’re for everyone!