System z Virtualization and Workshop Bootcamp System z Unit 1: System z Virtualization Overview 1.1 - Hardware / Architecture 2007 IBM Corporation Mainframe Paradigm Mainframe original design point: Share everything Support of mixed workloads Virtualization helps enable: Simplification High utilization Intelligent management This creates a foundation to: Help customers solve On Demand business problems Extend mainframe capabilities to intelligently manage virtualized resources across the enterprise Virtu ualization Engine 2.0 Mainframe multi-dimensional virtualization System z9 Virtual access Virtual management Physical & Virtual Resources Key virtualization features are designed in, not added on 2 Alejandro Saucedo 1
System z Virtualization and Workshop System z channel subsystem improves I/O performance Channel Subsystem System Assist Processors (SAP) I/O Channels (RISC Processors) Shared I/O capability VM z/os z/os Significant I/O Offload Address limit checking Channel path management I/O busy conditions Manage Interrupts Dynamic path reconnect Transfer data Receive CU sense information Channel subsystem monitoring Channel Subsystem I/O I/O I/O I/O Hypervisor (PR/SM TM) SAP SAP C h a n n e l s This benefits all logical partitions including z/os and 3 2007 IBM Corporation Where System z Excels Running multiple diverse workloads at high utilization Heavy I/O content, large amounts of data High volume, high transaction rates, large number of users, unpredictable web workload Workloads that require any or all of these attributes: high availability, scalability, reliability, and security Virtualizing many underutilized servers with server consolidation 4 Alejandro Saucedo 2
System z Virtualization and Workshop System z Servers CPU Virtualization Physical CPs are shared or dedicated Shared LPARs are defined using three ideas: s (s) Weights (for shared LPARs) Capped / Uncapped. Advantages Resources are not idle unless LPARs are capped or use dedicated CPs. Event driven CPU virtualization allows CPU utilization to be increased lowering cost Dedicated Physical CPs Shared Physical CPs CP CP CP CP CP CP CP CP CP CP z/os 1 z/vm 1 z/vm 2 z/os 2 z/os 3 Weight - 50 Weight - 15 Weight - 10 Weight - 25 Example: 5 LPARs Maximum 60 LPARS 5 2007 IBM Corporation System z Virtualization and Workshop System z Servers I/O Virtualization Benefit Allows channel sharing Lowers cost EMIF/MIF z/vm z/os test LP 1 LP 2 LP 3 PR/SM - EMIF/MIF Control Unit Devices 6 2007 IBM Corporation Alejandro Saucedo 3
System z Virtualization and Workshop System z Servers Network Virtualization IP Networking among virtual servers Improved performance in memory data movement Enhanced security - Data never flows outside the server Higher availability - Integrated into System z hardware, no external parts Lower cost - No external network, attachment, or cables Reduced time to market virtual networks can be provisioned i in seconds at no incremental cost z/vm z/os HiperSocket LAN z/os HiperSockets Improved performance in memory data movement No network latency One physical system only 7 2007 IBM Corporation System z Virtualization and Workshop z/vm Virtualization General Introduced in 1967 Approximately 3700 active licenses Support hundreds of guests Runs in an LPAR Virtual s 1-64 Virtual s Shared PCI-X Cryptographic support Virtual memory Over commit memory Share memory between guests Virtual network Virtual or real HiperSockets Virtual IP or Layer 2 Switch IEEE VLAN Support Dedicated or shared virtual disks Additional service machines Automated Console (PROP) TCP/IP stack TCP/IP VM - CP Shared I/O (MIF) HiperSockets PR/SM TM z/os IFL IFL IFL CPU CPU I/O I/O I/O I/O 8 2007 IBM Corporation Alejandro Saucedo 4
Consolidation on System z meets the challenge Potential savings up to 80% compared to x86 Sprawl DGTI Quebec on System z9 60 UNIX servers to 5 IFLs on z9 Increased capacity by over 2.5X Nationwide Insurance on System z9 250 Servers to 6 IFLs on z9 Will save $16M over next 3 Yrs Large environment on z10 760 x86 Servers to 26 IFLs Save up to 80% over3 Years Up to $56M in savings 5.1 X 80% Savings 1.0 X 760 x86 CPs 26 z10 EC IFLs Sun X2100 Single Core servers z/vm on System z10 EC Space Power People Cos Software Maint Software Maint Hardware Potential savings of up to 80% when consolidating to System z10 and versus distributed x86 Servers 9 *Comparison is versus x86 Blade servers without virtualization, reflecting a current-day consolidation. Reductions will vary by the number and age of the x86 servers being consolidated. System z10 and zseries Typical Architecture for On Demand Business L L L L L L L z/ C i i C C V i i i i i O M n n M M S n n n n n S S S u u u u S E u u u x Java x x x x x x z/vm z/vse z/os z/vm V4 LPAR LPAR LPAR LPAR L i n u x LPAR CP1 CP2 CP3 CP4 zaap IFL1 IFL2 IFL3 Standard Processors zaap IFL Engines IBM System z10 or zseries Server 10 Alejandro Saucedo 5
What: Virtual Machines Virtual Machine Virtual Machine Virtual Machine Hypervisor (z/vm Control Program) A virtual machine is an execution context that obeys the architecture The purpose of z/vm is to virtualize the real hardware: Faithfully replicate the z/architecture Principles of Operation Permit any virtual configuration that could legitimately exist in real hardware Let many virtual machines operate simultaneously Allow over commitment of the real hardware (s, for example) Your limits will depend on the size of your physical System z computer Virtual machine aka VM user ID, VM logon, VM Guest, Virtual Server 11 What: Virtual Machines in Practice? z/os CMS z/vse 32-bit 64-bit z/tpf Others Hypervisor (z/vm Control Program) Control Program Component manages virtual machines that adhere to the S/390 architecture and the z/architecture Extensions available through CP system services and features CMS is special single user system and part of z/vm Control Program interaction via console device 12 Alejandro Saucedo 6
Phrases associated with Virtual Machines In VM Guest: a system that is operating in a virtual machine, also known as user or userid Running under VM or Running on VM: running a system as a guest of VM Running second level: running a system as a guest of VM which is itself a guest of another VM A virtual machine may have multiple virtual s Sharing is very important In relationship to LPAR (partitioning) Logical Partition: LPAR equivalent of a virtual machine Logical Processor: LPAR equivalent of a virtual Running native or Running in BASIC mode: running without LPAR Note: Basic mode is not available on z890, z990, z9 or z10 Isolation is very important 13 Phrases Associated with Virtual Machines Virtual z/vm Control Program z/os or z/vse Virtual Virtual Virtual Virtual z/vm Control Program Logical Logical Logical Logical Logical Logical Logical Logical Partition Logical Partition PR/SM LPAR 14 Alejandro Saucedo 7
What: A Virtual Machine Virtual Machine z/architecture 512 MB of memory 2 s Basic I/O devices: A console A card reader A card punch A printer Some read-only disks Some read-write disks Some networking devices We permit any configuration that a real System z machine could have In other words, we completely implement the z/architecture Principles of Operation There is no standard virtual machine configuration 15 What: Device Management Concepts Dedicated or attached The guest has exclusive use of the entire real device. Virtualized Present a slice of a real device to multiple virtual machines Slice in time or slice in space e.g. DASD, crypto devices Simulated Provide a device to a virtual machine without the help of real hardware Virtual CTCAs, virtual disks, guest LANs, spool devices Emulated Provide a device of one type on top of a device of a different type FBA emulated on FCP SCSI 16 Alejandro Saucedo 8
How: VM User Directory Definitions of: USER LINUX01 MYPASS 512M 1024M G memory MACHINE ESA 2 CPU 0 architecture t CPU 1 s IPL 190 PARM AUTOCR CONSOLE 01F 3270 A spool devices SPOOL 00C 2540 READER * network device SPOOL 00D 2540 PUNCH A SPOOL 00E 1403 A disk devices SPECIAL 500 QDIO 3 SYSTEM MYLAN other attributes LINK MAINT 190 190 RR LINK MAINT 19D 19D RR LINK MAINT 19E 19E RR MDISK 191 3390 012 001 ONEBIT MW MDISK 200 3390 050 100 TWOBIT MW DEDICATE 1000 1000 17 Virtual Readers, Punches, and Printers Each virtual machine has: a virtual reader at virtual device number 00C like the in-box of an e-mail system, except more than just e-mail can be placed there. a virtual punch at virtual device number 00D Through your virtual punch, you can place a copy of an entire operating system into the system spool, then use the CP IPL command to load and run that operating system in your virtual machine a virtual printer at virtual device number 00E 18 Alejandro Saucedo 9
What: Processors Configuration Virtual 1- to 64-way Defined in user directory, or Defined by CP command A real can be dedicated to a virtual machine Control and Limits Scheduler selects virtual s according to apparent CPU need Share setting - prioritizes real CPU consumption Absolute or relative Target minimum and maximum values Maximum values (limit shares) either hard or soft Share for virtual machine is divided among its virtual s 19 z/vm CPU Resource Controls Highly Granular Sharing of System Resources Allocate system resources per guest image using SHARE command This is a highly flexible and self-managed function of the z/vm Control Program Reserve CPU capacity for peak usage Use it when needed Relinquish the cycles for other servers when not needed "Absolute guests" receive top priority The Virtual Machine Resource Manager can be used to monitor and adjust remaining capacity allocated to "Relative guests" z/vm Directory Entries (or on-the-fly commands) SHARE Lin1 ABSOLUTE 60% LIMITSOFT SHARE Lin2 ABSOLUTE 30% LIMITHARD SHARE Lin3 RELATIVE 300 LIMITHARD SHARE Lin4 RELATIVE 200 LIMITSOFT SHARE Lin5 RELATIVE 200 LIMITSOFT Absolute % 80 60 40 20 Absolute Guests Relative Guests Relative Share Lin1 Lin2 Lin3 Lin4 Lin5 0 0 z/vm Control Program 800 600 400 200 Notes: = limit can be exceeded if unused capacity is available (LIMITSOFT) = limit will not be exceeded (LIMITHARD) Alejandro Saucedo 10
What: Virtualization of Disks 101 D 100 A R/W R/W 1 R/O Minidisk Cache (High-speed, in-memory disk cache) 200 C R/O 2 R/W R/W Virtual Disk in Storage (memory) E Excellent swap device if not storage-constrained B01 3 R/W R/W Virtual Disk in Storage (memory) 100 100 B B01 z/vm TDISK: on-the-fly disk allocation pool 2B00 2B01 2B02 TDISK 1 TDISK space Dedicated Minidisk 1 Minidisk 2 Minidisk 3 Enterprise Storage Server Minidisk: z/vm disk allocation technology Notes: R/W = Read/Write R/O = Read Only 21 What: Data-in-Memory Minidisk Cache Write-through cache for non-dedicated disks Cached in central or expanded storage Pseudo-track cache Great performance - exploits access registers Lots of tuning knobs Virtual Disk in Storage Like a RAM disk that is pageable Volatile Appears like an FBA disk Can be shared with other virtual machines Plenty of knobs here too 22 Alejandro Saucedo 11
What: Virtual Networks Connecting virtual machines to one another Guest LAN QDIO or HiperSockets Virtual Switch Guest LAN Layer 2 or Layer 3 Connecting virtual machines to another LPAR HiperSockets Shared OSA Connecting virtual machines to the physical network Dedicated OSA device Virtual Switch Layer 2 or Layer 3 23 Networking options for guests ESCON CTC ROUTER OSA OSA OSA CH CH OSA CH z/vm vswitch Guest LAN TCP/IP TCP/IP TCP/IP z/vm TCP/IP Guest LAN VCTC or IUCV HiperSockets TCP/IP TCP/IP z/os LPAR ESCON OSA Card ESCON CTC Virtual CTC IUCV Guest LAN Virtual Switch 24 Alejandro Saucedo 12
IBM Tivoli OMEGAMON XE for z/vm and Announced* on October 10, 2006 Combined product offering that monitors z/vm and for System z Provides work spaces that display: Overall system health Workload metrics for logged-in users Individual device metrics LPAR Data Provides composite views of running on z/vm Supported on z/vm V5.2 + Performance Toolkit for data collection Available: 13 October 2006 * Refer to IBM Software Announcement 206-251 System z Virtualization and Workshop Bootcamp System z Unit 2: The Control Program (CP) 2007 IBM Corporation Alejandro Saucedo 13
Control Program and Guest OS's Guest OS's System Page Spool C M S mini disks data C M S z / O S L I N U X V M V S E T P F System work Communication VM/CP virtual devices real devices 27 What are Virtual Machines? z/vm uses real resources to create virtual machines that include s, memory, I/O devices, and network devices Virtual machines run as if a guest system was running on the real hardware Virtualization Technology creates an illusion that z/vm uses to virtualize hardware components VM allows users to run multiple copies and different types of operating systems on the same mainframe system 28 Alejandro Saucedo 14
Storage Virtualization Physical Storage Direct Access Storage Devices (DASD) are the main storage device Minidisks are the partitions of the DASD storage device These are the physical storage devices that can be virtualized to obtain virtual storage devices Virtual Storage Virtual disks are high speed disks that perform and are capable of the same operations as the physical storage devices If you have a CP failure or shutdown all virtual devices are lost Virtual storage increase performance and can increase total size of storage devices 29 The Virtual Machine devices Devices Real or Virtual 1 Attached and Dedicated devices 2 Mini-disks 3 Logical devices 4 Spool devices 5 Special OSA Network E20/E21 280 180 Standard "in out err" devices qdqqvjpdfdfd sqqdqdddhjh, q qsdqsdfdhf,jk DIA L SPOO L 535A 150 MDISK 150 3390 0001 005 SPOOL 00C DEDICATE 180 280 DEDICATE D00 FBC0 DEDICATE 600 0E20 DEDICATE 601 0E21 SPECIAL 080 3270 SPECIAL C10 CTCA TCPIP 30 Alejandro Saucedo 15
Console Status Messages CP READ - The Control Program (CP) is waiting for a command. If you accidentally hit PA1 (alt and F1), or enter stop as a command, you can enter b for begin to get out of it. VM READ - CMS is waiting for a command. RUNNING - Either something is being worked on or the system is waiting for a command. MORE... - There's more information to be displayed. To show it, press clear (Esc or Break on some systems). To keep the information on the screen (the screen will scroll on eventually), press enter. HOLDING - The system is waiting before it shows more information. Press clear (Esc) to continue. 31 z/vm Architecture 32 Alejandro Saucedo 16
Linking to Disk ( CP Command) Linda (owner) 191 MDISK 191 3390 110 10 440RES MR Don (sharing) LINK LINDA 191 291 RR ACCESS 291 B 33 DISKMAP Exec 530W01 $ALLOC$'s A01 mdisk $PAGE$'s A02 mdisk AUTOLOG1's 191 mdisk GAP CMSUSER's 191 mdisk Execute DISKMAP (diskmap user direct) XEDIT USER DISKMAP (find gaps) XEDIT USER DIRECT (add new entries) EXECUTE DISKMAP (verify no new overlaps) Put Directory Online VOLUME USERID CUU DEVTYPE START END SIZE 530W01 $ALLOC$ A01 3380 0000 0000 0001 $PAGE$ A02 3380 0001 0003 0003 AUTOLOG1 191 3380 0004 0004 0001 $TDSK$ A02 3380 0001 0016 0016 OVERLAP 17 18 2 GAP CMSUSER 191 3380 0019 0019 0001 MAINT 125 3380 0000 1769 1770 OVERLAP 34 Alejandro Saucedo 17