Introduction to the new mainframe: Large-Scale Commercial Computing © Copyright IBM Corp., All rights reserved. Chapter 3: Scalability

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 2 Chapter objectives Upon completion of this chapter the student should be able to understand: What scalability means Differences between scaling in and scaling out Mainframe’s hardware relationship with scalability Software scalability levels Parallel Sysplex relationship with scalability Workload management main concepts

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 3 Introduction to scalability Some definitions:  Hardware capability of a system to increase performance under an increased load when resources are added (From Wikipedia Encyclopedia  Software ability to grow with your needs. A scalable software package means that you only buy the parts you need, and that it has the ability to grow by adding on as you grow. (From The Concise Tech Encyclopedia:

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 4 Scalability concepts  Scalability approaches Scale vertically or scale up : add resource to a single node in a system Scale horizontally or scale out : add nodes to a system

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 5 Scalability concepts  Scalability influences Vertically growth : Upgrade the installed server processor capacity to a larger one within the same family Horizontally growth through Parallel Sysplex: add processor capacity by adding more servers in a cluster.

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 6 Scalability influences : be realistic IBM System z Nways Relative Performance Sublinear Performance Linear growth

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 7 Scalability concepts Provisioning Provisioning is the end-to-end capability to automatically deploy and dynamically optimize resources in response to business objectives in heterogeneous environments.  helps to respond to changing business  is a critical step to being able to then orchestrate the entire environment to respond to business needs on demand.

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 8 IBM System z implementation – Hardware scalability System I/O Bandwidth CP Us GBs ITRs for 1-way System z9 109* zSeries 990 zSeries 900 Generation 6 Generation GB/sec 96 GB/sec 24 GB/sec 256 GB 64 GB ~ way 32-way 54-way 512 GB Balanced System CPU, nWay, Memory, I/O Bandwidth* *z9-109 exploits a subset of its designed I/O capability ITR = Internal Throughput Rate

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 9 IBM System z processors Z9 Model 38 Configuration  1 GB/sec  500 MB/sec  333 MB/sec  Speed set based on I/O type Processor Book 3 FICON Express2 I/O Ports OSA-Express2 I/O Ports 2.7 GB/sec Memory Cards L2 Cache 16 STIs PU Memory Cards L2 Cache 16 STIs PU Ring Structure 8 MBA Fanout Processor Book 0 I/O Card Processor Book 1 ESCON I/O Ports Crypto Express2 ICB-4 2 GB/sec Memory Cards L2 Cache 16 STIs PU Memory Cards L2 Cache 16 STIs PU Ring Structure Processor Book 2 8 MBA Fanout Note: Each MBA Fanout card has 2 STI ports. STI connectivity is normally balanced across all installed Books MBA supports 2 GB/sec for ICB3 and ICB-4 and 2.7 GB/sec for I/O channels. ICB-3 actually run at 1GB/sec STI-MP & STI-A8 STI-MP & STI-A8 STI-MP & STI-A8 STI-MP & STI-A8 STI-MP & STI-A8 STI-MP & STI-A8 STI-MP & STI-A8 STI-MP & STI-A8 I/O Cage

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 10 Operating system scalability

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 11 Scalability of IBM System z – Parallel Sysplex ESCON/FICON Coupling Facility SYSPLEX Timer Shared Data Z9 BC Z9 EC Z9 BC

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 12 Parallel Sysplex  Serialization : to coordinate access to resources Enqueuing : serialization for a large number of resource Locking : extremely quick, but only for a small number of resources  Communication : Cross-System coupling facility provides simplified multisystep management services withjin a base sysplex configuration

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 13 Parallel Sysplex (Cont...)  Data sharing and Coupling facility

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 14 Parallel Sysplex (Cont...)  Workload distribution Manually Round robin Dynamic workload distribution Workload Management-driven application servers

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 15 Provisioning  Dynamic Resource Distribution Up to 60 logical partitions (LPAR) Each LPAR is completely isolated and protected Processors can be shared Workload Manager (WLM) can distributed processing resources across LPAR clusters I/O bandwith can be shared amongs LPARs under WLM control Each LPAR has own physical memory, it can be altered dynamically

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 16 Capacity On Demand (CoD) Different CoD options:  Capacity Upgrade on Demand (CUoD)  Customer Initiated Upgrade (CIU)  On/Off Capacity on Demand CoD encompasses the various capabilities for you o dynamically activate one or more resources in your server as your business peaks dictate.

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 17 Workload Manager (WLM) The idea of Workload Manager is to make a contract between the installation (end user) and the operating system. The installation classifies the work running on the z/OS operating system in distinct service classes and defines goals for them which express the expectation how the work should perform. WLM uses these goal definitions to manage the work across all systems of a parallel sysplex environment.

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 18 WLM Components

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 19 WLM (Cont...)  Work unit identification Managing Units of Work on z/OS (e.g. A transaction)

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 20 WLM (Cont...)  Defining the service level Importance of a goal Adjustment routine Workload Management controls

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 21 WLM (Cont...)  WLM extensions  Intelligent Resource Director (IRD) CPU LPAR management Dynamic channel path management I/O Priority

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 22 Summary The New Mainframe: is scalable On hardware and software level Parallel Sysplex is involved WLM

Introduction to the new mainframe © Copyright IBM Corp., All rights reserved. 23 Key terms in this chapter Access time CF CoD Communication Coupling facility Enqueuing IRD ITR Locking LPAR Parallel Sysplex Provision Scalability Scale in Scale out Serialization SLA WLM Workload