Mainframe alternative Solution Brief. MFA Sizing Study for a z/os mainframe workload running on a Microsoft and HP Mainframe Alternative (MFA)

Transcription

1 Mainframe alternative Solution Brief MFA Sizing Study for a z/os mainframe workload running on a Microsoft and HP Mainframe Alternative (MFA)

2 Mainframe alternative Solution Brief MFA Sizing Study for a z/os Mainframe Workload Running on a Microsoft and HP Mainframe Alternative Introduction A major company in the medical supplies sales and distribution business recently moved all of its IBM z/os workloads over to a Mainframe Alternative (MFA) system provided by HP, Microsoft and Micro Focus. The company reduced the ongoing cost of IT operations by replacing very expensive legacy infrastructure. It also improved the speed, quality and overall agility of application software development and maintenance. This customer s IT operations and application development and maintenance are outsourced to Dell Perot Systems who delivered this project. HP is the preferred provider of hardware and related infrastructure. Micro Focus Server Enterprise Edition (Micro Focus Server EE) running on the Windows Server OS, and Microsoft SQL Server relational database management system, had been chosen as the Mainframe Alternative (MFA) solution platform. Prior to this study, Dell Perot Systems had migrated the customer s data and programs, made required changes, and compiled and tested the programs using Micro Focus COBOL. Dell Perot Systems needed to size the production MFA hardware to be purchased, to determine the best configuration for the hardware and software, and to assess overall system manageability. This sizing and configuration study was a critical step before the start of integration testing and end-user acceptance testing, for which the production HW/SW configuration would be used. Also, it was time to put to rest the lingering doubts expressed by some of the mainframe systems management and technical staff about whether or not a mainframe alternative system, built on industry standard servers, was up to the task - in particular, the task of high volume data I/O for which many believe that mainframe systems are un-matched. In order to answer these questions, Microsoft and Micro Focus assisted Dell Perot Systems with a sizing and manageability study, conducted at a Microsoft Technology Center ( equipped with the necessary HP computer systems, networking and other supporting hardware. This paper describes that study and its results; the conclusion of which is seen in charts 1 and 2. Charts 1 and 2 compare the system cost and throughput delivered by an IBM mainframe System z computer rated at 617 MIPS running the customer workload under z/os, and that same workload running on a MFA system. The charts show that the MFA system delivered better performance (1257 versus 1050 customer order lines per minute) than had ever been achieved on the existing IBM mainframe. The charts also show that the cost of the MFA HW and systems SW is less than half of the infrastructure cost of the mainframe. Application Service Level Commitments In order to maximize savings, a primary goal of this project was to remove the mainframe environment. This required the entire customer s z/os applications and workloads to be re-hosted to Micro Focus Server EE running on a Microsoft and HP Mainframe Alternative (MFA) system. Also, as is not uncommon, adequate performance of one particular application - in this case the order entry application - was critical to the business and the project. Customer orders are processed in near real-time as they arrive during the course of the day. Each day s orders need to be completed in time for overnight warehouse picking and packing, and loading onto trucks for next day delivery. In order to meet this SLA (Service Level Agreement) commitment, a certain minimum rate of customer order lines processed per minute needs to be achieved. Therefore the key SLA metric is order lines processed per minute. The normal day s peak rate is about 800 order lines per minute which can be achieved with about 100 active online users doing other work. The highest rate ever achieved on the z/os system was 1050 order lines per minute, but to achieve this required no other active workload and essentially all system resources dedicated to order processing. Re-host vs Re-write Mainframe applications can be migrated to a mainframe alternative by several means. Re-writing the application code in a new language for the new platform is one way. However, re-hosting the existing code to a mainframe compatible runtime environment can usually be done with less risk and lower cost. This is discussed at migration.mspx Charts 1 and 2: Mainframe and MFA system cost and throughput

3 Companies are reducing operational costs, increasing business efficiency, and improving business agility by modernizing their mainframe applications to a solution based on Micro Focus, Microsoft, and HP products. In addition to a flexible platform to support business critical computing needs for years to come our combined application migration solution reduces the risk of transition from a mainframe. John Pickett, Worldwide MFA Program Manager, HP Key Order Entry Application Characteristics Order Entry is a CICS application written in COBOL. Its defining performance characteristic is that it makes a high number of SQL database calls per customer order line processed (224 in the test data used for this study), and also logs order completion records to VSAM files. On z/os, Omegamon reported 11.6 elapsed seconds per order were spent waiting for DB2, which equates to.5 seconds per order line. Therefore aggregate elapsed SQL call time per transaction is the most significant component of order entry transaction processing time, and overall order lines per minute throughput. Another important characteristic to be noted that affects throughput is the above mentioned fact that Order Entry updates both SQL database tables and VSAM files. A single system level transaction must wrap both the SQL and VSAM update into a single ATOMIC event, such that either all the updates happen, or none. The system sizing needs to accommodate this additional processing which introduces more contention within the system and takes more time. The order entry application also uses CICS Transient Data Queues (TDQs). Lastly, the order entry transactions generate order confirmation transactions (via EXEC CICS START) that send a notification back to the customer who entered the order. To allow these order confirmations to run in a timely manner requires that application program execution processes are available to run these confirmation transactions even when order entry is running at maximum concurrency. Data Integrity When one program updates only one resource, e.g. a database, it is relatively easy to guarantee transaction integrity. In this order entry application, multiple CICS programs update multiple tables as well as VSAM files. All of these updates were managed as a single transaction on the MFA system, as they were on the mainframe. Test Environment and Platforms All testing was done on 64-bit Windows Server 2008 Enterprise using 64-bit SQL Server 2008 and Micro Focus Server Enterprise Edition with 64-bit support. The 64-bit environment provides advantages even if compiled application programs are still in 32-bit. The 64-bit OS provides the advantage of larger memory spaces for disk file and network data caching and buffering, and for storage of other artifacts managed by the OS and by SQL such as compiled SQL statement and execution plans. Also on the 64-bit OS the private area address space available to 32-bit applications is substantially larger than on the 32-bit version of the OS, approximately 3.8GB versus about 2GB. While most mainframe application programs might not be able to take advantage of this additional memory address space, it can be of value to processes such as the Micro Focus communication process that handles 100 s or 1000 s of the TN-3270 connections and manages CICS user sessions. All servers were interconnected on a dedicated Gigabit Ethernet network with no traffic other than that of the tests. All servers had two PCIe bus 1GB Ethernet connections allowing two I/O paths for network traffic. This traffic was multiplexed over these paths by the Multi-Path I/O feature of Windows Server For data file access all servers had a fiber-optic host bus adapter connection to the Storage Area Network (SAN). The system (the OS, SQL, Micro Focus Server EE, etc.), programs and other libraries, e.g., PARMLIB and other files, were placed on server Direct Attached Storage (DAS), as was SCRATCH. Preparation Before the start of any testing with the customer application, Micro Focus ran a benchmark application on various HP servers and configurations of those servers at the Microsoft Technology Center (MTC). The result of these tests formed the basis on which to select initial and alternative machine configurations on which to test the customer workload. The Microsoft Technology Centers are available to customers who wish to envision or test concepts. For this project, the MTC provided the required hardware and software, as well as expert installation and configuration assistance. ISC Between Two Regions The requirement to always be able to run order confirmation transactions that are STARTed by order entry was met by running the Micro Focus equivalent of a second CICS region. An ISC (InterSystem Coupling) connection was set up between these regions so that an EXEC CICS START issued by order entry would initiate an order confirmation transaction that ran in the second region. The following primary test configurations were chosen for the actual customer workload sizing study: 1. An entry level MFA system, to establish a throughput baseline. A single 8 CPU HP BL465 blade server (two quad core AMD Opteron processors), for the transaction and SQL database servers. 2. A scale-out configuration with separate application servers and database servers. Two HP BL465 blade servers, one running the transaction server, the other SQL Server. 3. A scale-up MFA configuration with a single very powerful server. A single 32 CPU HP DL785 server (8 quad core AMD Opteron processors), for the transaction and database servers. 4. Deployment in a virtualized environment, in a Hyper-V Virtual Machine (VM).

4 A Hyper-V virtual machine with 4 virtual CPUs running the transaction server, and SQL Server running native on the host machine. Data was on pass-through disk (SAN based Logic Volumes), not in VHDs (virtual hard disks) Figure 1 displays the OS Performance Monitor data from a preparatory test run on the entry level 8 CPU MFA system. Graphed in figure 2 are processor CPU busy (8 CPUs running at about 70% busy), CPU privileged time and SQL transactions per second. Several hundred, maybe thousands, of other measurement are available. Entry Level System Scale out Configuration Scale up Configuration Scale Out Virtualized Configuration Figure 1: Leveraging the power to improve

5 Customers today are faced with challenges of doing more with less. Together with Microsoft and HP we are able address the challenges of budget, time to market, performance and retention of intellectual property that are locked away in these core business applications. Delivering a highly performant enterprise platform, ready to meet the challenges of this new decade of computing requirements Peter Duffell, Vice President Strategic Partners, Micro Focus In comparison, the single HP BL465 8 CPU (2 quad core processors) blade server configuration was able to achieve 623 order lines per minute. The throughput of the Hyper-VM configuration was 408 order lines per minute. Chart 3 shows the throughput achieved by these systems, and also the throughput delivered by the IBM z/os mainframe and the 32-CPU DL785. Figure 2: Several hundred measurements are available Note that the BL465 blade system (and the VM solution), which achieved about half the mainframe throughput, is a single 8 CPU blade server with a retail cost of less than $10,000 including a blade chassis enclosure. The DL785 server, which exceeded the mainframe throughput, costs less than $100,000. This hardware configuration and cost information is available at under Large Enterprise Business >> Blades. Information about the DL785 is at under Large Enterprise Business >> Servers. Test Setup and Execution Dell Perot Systems brought its customer s application and data to the MTC, and also tested customer transaction data from which to generate a simulated online workload. The Microsoft MTC staff set up the HW configuration and installed Windows Server 2008 and SQL Server 2008 as requested by the study team. While Micro Focus installed and configured Server EE, Microsoft added OS features to be used in the testing and made elected configuration changes. Dell Perot Systems installed the applications and data on these systems. An important Micro Focus Server EE configuration parameter was to set the number of CICS applications that can run at the same time. This is similar to the concept of concurrent CICS tasks, i.e. setting the number of CICS transactions that can run at the same time. The throughput effect of concurrency settings is discussed later in this paper. While Dell Perot Systems ran the application, Micro Focus engineers looked at real-time performance information made available by Server EE and Microsoft staff ran Windows Server Performance Monitor and SQL Server performance reports. Both Micro Focus Server EE and Performance Monitor Trace Logs were also generated and studied after each test. Result The best performance (1257 order lines per minute) was achieved on the scale-up MFA configuration of a single HP Proliant DL785 server with 32 CPUs (8 quad core processors). This performance was achieved with an average CPU utilization of about 50% across the 32 CPUs in this MFA system. The unused CPU time represents head room to make the system more available and provide better service to endusers. This head room is also the capacity to support growth in the business, i.e. to process more order lines per minute or other business initiatives. Chart 3: Order processing rate of alternative systems Scale-up shown best for deployment of this workload The single 32-CPU server configuration of one high CPU count server running a single OS system image proved best for this workload. This order entry application had two characteristics that argued for a scaleup deployment. Two major resource types were shared, VSAM files and CICS Data Queues. Micro Focus Server EE has the ability to share access to these resources between applications running on separate servers, but such sharing requires additional network hops between servers. This adds to the elapsed processing time of transactions using these resources. The order entry application made many calls of this type. Because of the very large number of SQL calls made in the processing of each order, most transaction elapsed time is spent waiting for a SQL call response. Therefore the elapsed time of those calls must be minimized. Local calls to an SQL Server on the same machine take less time than calls across a network, even a dedicated 10GB Ethernet network. While elongation of each transaction s execution time due to network calls can be mitigated by running more transactions concurrently, returns are limited by contention for access to

6 shared resources. For example, concurrent access to the same row in an SQL table or concurrent CICS TDQs access. The choice to deploy SQL Server and the application on the same server obviated the possibility to run the application across a scale-out cluster of servers, all using a single separate SQL Server cluster or machine. For the above reasons, a scale-up deployment was best for this workload, which was proven in these tests. In this scale up deployment, transaction concurrency was found to have a measurable effect on throughput. Too low a concurrency did not adequately utilize the system. Too high a concurrency increased task switching overhead, which will eventually decrease throughput. For example, in one test, throughput improved by 6% when 16 concurrent transactions were affinitized to run on 8 CPUs instead of on 16. Performance management tuning and experimentation is necessary to find the optimum concurrency for any particular workload or workload mix. Windows System Resource Manager, a feature of Windows Server 2008, was used to limit usage to only certain CPUs, and to affinitize specific workloads to only certain CPUs. Additional tests on the DL785 achieved 87% of the 1257 lines per minute peak performance (1089 lines per minute) while using only 16 CPUs for Micro Focus Server EE and 8 CPUs for SQL Server. This number was increased to 93% of peak (1167 lines per minute) by further tuning workload affinity to specific CPUs. Microsoft and Scale-Up Microsoft and HP support both scale-up and scale-out solutions. Since scale-out is more often used, especially for deployment of modern java and.net applications, it is worth a few words of explanation about why scale-up was best here. Microsoft s frequent recommendation of scale-out presumes a typical modern workload designed and programmed as a distributed system using modern SQL programming concepts in which relatively few but more complex SQL statements ask the SQL server to do significant work on behalf of the application program. This creates less work in the application (and often less code), more work for the SQL Server, and fewer calls between them. Most z/os applications are not programmed this way. A typical z/os application makes a large number of SQL calls, often with very simple SQL statements, sometimes because they were originally designed and written for VSAM. What about Scale-Out Deployment? Scale-out is the idea to deploy a single application across multiple server systems that run in parallel, which can be done with an IBM mainframe Parallel Sysplex. One advantage of a scale-out approach is its inherent redundancy, which leads to near 100% application availability (as opposed to individual server availability). Another advantage of scale-out is to provide the most processing power for the least cost (the best processing power to cost ratio and therefore higher value), because each individual server can be used more as a limited capacity commodity server. Considering the possibility of a scale out architecture, tests were performed on 8 CPU HP BL465 blade servers with two quad core processors. These blade servers had fiber optic host bus adapters and connections comparable to those on the 32-CPU DL785 and were connected to the same DASD SAN. These tests showed that the 8 CPU blades had essentially the same performance characteristics as the 32-CPU DL785 up to the limit of 8 CPUs per blade. Available CPU time was shown to be the throughput limiting factor, and performance on the 8 CPU blade servers was essentially the same as on the DL785 when the workload was restricted to using only 8 CPUs. An HP blade system could be a good choice for a customer with a less demanding workload, or a workload more suited to a scale out deployment. Scale-Out Workloads? The workloads best suited for scale-out deployment are either share-nothing workloads, or workloads that share data stored in an SQL Server where access concurrency is managed by a single instance of a database management system deployed in a cluster of SQL Servers (or a single server in simpler deployments, with lower availability and elapsed recovery time requirement). What about Virtualization and Deployment in Virtual Machines? Virtualization is a powerful concept with many benefits, and is very much in vogue today. Therefore the customer workload was also run on Micro Focus Server EE running in a virtual machine. The application ran very well (408 Order Lines Per Minute) up to the limit imposed by the 4 virtual CPU maximum per virtual machine. Performance in a virtual machine was similar to that in a real machine with only 4 CPUs, subject to the following caveats: Real CPU time is available in the physical host machine in order to service the 4 virtual CPUs in the VM. Data that is continually and rapidly expanding is not stored in a dynamically expanding virtual hard disk drive (VHD). Generally, production data should be stored either in pre-allocated fixed size virtual hard disks or, for even better performance, with high demand access, stored on physical disk volumes or SAN logical volumes that are directly allocated (and therefore dedicated) to the virtual machine in which the application is running. The Hyper-V pass-through disks capability directly allocates disk volumes to virtual machines. Following the above listed guidelines, the order entry application ran very well in these tests in a Hyper-V virtual machine. These and other tests done by Micro Focus and Microsoft suggest that deployment in

7 Organizations with mission-critical mainframe systems are moving to Windows Server and SQL Server to more competitively address today s IT requirements and reduce costs. Together; Microsoft, Micro Focus and HP provide a comprehensive Mainframe Alternative (MFA), that provides a powerful and cost-effective choice for IBM enterprise mainframe customers. Bob Ellsworth, Director, Enterprise Platform Modernization, Microsoft a virtual machine could be well suited to application workloads that demand 4 CPUs or less. Great benefits can be gained in application testing in virtual machines. At the end of each VM-based test, all disk changes can be simply discarded, thereby very quickly restoring the system to exactly the state it had before the test. Quality can be improved because time can be saved, allowing more tests to be run using machine change snapshots or differencing disks that can be kept, merged in or discarded, at the end of each test run. VM on Windows, or What is Hyper-V? Hyper-V is the virtualization technology available in Windows Server Similar to IBM s z/vm providing virtual machines in which one can run, e.g., z/os, z/vse or another OS that would run on the real hardware, Hyper-V provides virtual machines in which one can run the Windows OS (server or client) or anther OS such as certain versions of Linux. Scalability Since throughput was measured on a virtual machine with 4 virtual CPUs, and on real machines with 8 real CPUs, 32 real CPUs and with affinity to only 16 CPUs on the 32 CPU system, it was possible to take a look at the CPU scalability of this workload. These four alternatives are shown on the scalability in chart 4. Chart 4: Workload scalability as a function of CPU count (virtual CPUs in the 4 CPU case, and affinitized CPUs in the 16 CPU case) The above chart shows fairly linear CPU scalability, with an about 2:1 ratio between CPUs and throughput. In the case of moving from 8 to 16 CPUs, throughput goes up about half as much as the increase in CPU count. As the number of CPUs was doubled from 8 to 16 (a 200% increase), throughput went from 600 to 1050 (over 150%). Regarding the other data points, it should be noted that the CPUs were not saturated in all cases, nor were they equally busy in all cases. For example, the four virtual CPUs were running at nearly 100% busy, the 8 CPU system s CPUs were running near 80%, and the CPU utilization on the 32 CPU test was about 50%. What is a CPU? It s important to clarify what is meant by CPU in the context of this paper, and to differentiate CPU from processor and processors Core. Historically the P in CPU stood for processor and the terms were often used interchangeably. Today AMD, INTEL and others sell products they call processors, e.g. an Opteron or XEON processor, with multiple processor cores. So which is the CPU - the processor or the processor core? Understanding a CPU to be that entity which runs an OS thread of execution, and that a quad core processor can concurrently run four OS threads, the # of CPUs is the # of cores. Hence this paper refers to a system with 8 quad core Opteron processors as a 32 CPU system. In fact, today s processor cores contain more than CPUs, for example memory cache. A Manageable Solution In addition to the extensive systems management and performance information provided by Windows Server and SQL Server reporting tools, Micro Focus Server EE exposes a wealth of management data. It provides key system data through standard Windows mechanisms allowing its measurements to be combined with OS and SQL data in tables, graphs or logs, or in real-time displays. This integrated set of performance data can be readily consumed by standard management tools such as Microsoft s Systems Center / Operations Manager. Micro Focus Server includes a management pack that provides performance data to the Operations Manager. Conclusion A higher rate of order processing was achieved on a Microsoft and HP MFA system than this customer has ever seen under z/os on an IBM mainframe. To deliver this performance, Micro Focus Server EE used much less than the full capacity of the chosen scale-up MFA system. This gives room for growth and room for other workloads that need to run concurrently with order processing. As a result of this study, Dell Perot Systems ordered an HP Proliant DL785 server to run Micro Focus Server EE on Windows Server 2008 and with SQL Server 2008 to replace their System z mainframe running z/os CICS and batch. Due to the service provided by Microsoft, Micro Focus and HP, Dell Perot Systems was able to do this confidently knowing that they would be able to deliver on their service level commitments. Now that the ongoing cost of IT operations infrastructure has been reduced by more than half, a larger percentage of the customer s IT budget is available to improve services offered to business users who can, with better data and more capable applications, improve the business. While moving to a modern industry standard infrastructure, the customer has preserved the unique IP value contained in their custom order management system. Additionally, customer application

8 The Microsoft and Micro Focus technology platform provides an extensible, high performance and flexible solution compared to the mainframe environment. The migration has established a cost-efficient, powerful and secure computing platform to drive future growth and innovation. In addition, the utmost professionalism and efficiency displayed by the project team in this complex and mission-critical project was very impressive. Pete Fuson, Client Executive, Dell Perot Systems development and maintenance has moved to a modern, integrated development environment in which applications can be created, maintained and enhanced to deliver greater business value in less time and with greater quality. Credits Microsoft s Enterprise Platform Modernization mainframe alternative program information may be found at Mainframe/. HP Mainframe Alternative server information is available at hp.com/#product/ under Large under Large Enterprise Business >> Servers. Micro Focus Server Enterprise Edition can be seen at microfocus.com/products/server/serveree.asp. This paper was written by ztox Solutions Alternatives LLC, whose professional staff supported this project. ztox helps mainframe users envision the MFA possibility and to select their best path forward considering customer needs, resources and objectives. ztox also specializes in Windows Server system management, especially performance management. See ztox at System Software Operating System - Windows Server 2008 Enterprise DBMS - SQL Server 2008 TP Monitor - Micro Focus Server Enterprise Edition Batch (JCL) processing - Micro Focus Server Enterprise Edition Security - Windows Server integrated security also as used by Micro Focus Server Enterprise Edition and the SQL Server DBMS Systems Management tools integral to Windows Server, SQL Server and Micro Focus Server Enterprise Edition all of which can be exposed to centralized management, e.g., to Microsoft Systems Center / Operations Manger Hardware Systems HP Blade system using 8 CPU HP Proliant BL465 blade servers (2 quad core AMD processors) HP Proliant DL CPU high scale rack mount server (8 quad core AMD processors) Fiber optic access to DASD on SAN Dedicated Gigabit Ethernet network between MFA servers Network and SAN access on PCIe bus MFA Capabilities Used in the Tests Below are listed some of the MFA (MainFrame Alternative) capabilities of note that were used in this study. Many additional capabilities not listed below are also provided by this MFA solution. Some Micro Focus Server Enterprise Edition features used: IBM CICS compatibility, including: o TN-3270 network support o CICS terminal usage compatibility for logon and transaction entry/interaction User transactions are submitted through standard TN-3270 emulators o CICS command support, e.g., EXEC CICS LINK/START/READ/etc., and EXEC SQL o Multi-tasked transaction management in multiple application execution processes Shared transactional access to data in VSAM and SQL and use of TDQs o The equivalent of IBM CICS MRO (Multi Region Operation) InterSystem Communication (ISC) between regions z/os COBOL compatibility IBM z/os JCL compatibility (to run supporting batch jobs) Some Windows Server 2008 features used: Discreet OS address space based process management, similar to MVS address spaces in z/os o Memory isolation between transaction monitor and application software and between various concurrently running application programs Multi-task dispatching of CPU resources to contending mainframe application workload processes (regions), communications processes (TN-3270), the SQL database management systems, VSAM file access and other processes running concurrently on the OS High CPU count thread dispatching and management High performance TCP/IP networking Windows Systems Resource Manager to restrict workloads to use only certain CPUs and to generate SMF-like workload accounting records Integrated security for user authentication and resource access authorization o Domain based security both within the primary MFA server and for client and service access to protected resources on the MFA system

9 Performance monitoring using Windows Server 2008 Windows Reliability and Performance Monitor real-time displays to measure, monitor and report systems activity and application use of system resources, including performance logs for after the fact reporting and analysis SAN based storage of all application data, with complete physical disk failure recovery provided by the SAN (via RAID redundancy) Distributed Transaction co-ordination between multiple resources Multi-Path I/O for parallel multiple channel access to data on SAN (similar to multiple mainframe channel paths to DASD) o Higher performance Some SQL Server 2008 features used: High performance transacted relational data access Database partitioning and distributed data file location o Separation of workspace and logs from production table data Shadow copy support for database backup while running production o Via Windows Server Volume Shadow Copy service SQL Log based short time-window disaster recovery Location transparent SQL client access to SQL server on the same or a separate server computer o Redundancy based availability in the case that one path might fail File system access control list based security to control access to all disk based systems resources File Systems symbolic links allowing data location to be segregated into meaningful groups with friendly names and with essentially unlimited space expansion capability (alternative to cumbersome and obsolescent drive letter based file locations) Disk space usage quotas For additional information please visit: Micro Focus. All Rights Reserved. Micro Focus is a registered trademark of Micro Focus. Other trademarks are the property of their respective owners.