IBM BladeCenter PS703, Technical Overview And Introduction, Page: 106 / 198

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IBM BladeCenter PS703 and PS704 Technical Overview and Introduction
3.2 POWER Hypervisor
Combined with features designed into the POWER7 processors, the POWER Hypervisor
delivers functions that enable capabilities, including dedicated processor partitioning,
micro-partitioning, virtual processors, IEEE VLAN compatible virtual switch, virtual SCSI
adapters, virtual Fibre Channel adapters, and virtual consoles.
The user interface into the POWER Hypervisor on POWER-based blades has traditionally
been through the Integrated Virtualization Manager or IVM. Now a second method of systems
management is available, the Systems Director Management Console or SDMC. The SDMC
brings additional capabilities to POWER6- and POWER7-based blades that brings them
closer to traditional rack-based POWER platforms. Additional details can be found in
Chapter 5, “Systems Director Management Console” on page 151.
The POWER Hypervisor technology is integrated with all IBM POWER servers, including the
POWER7 processor-based blade servers. The hypervisor orchestrates and manages system
virtualization, including creating logical partitions and dynamically moving resources across
multiple operating environments. The POWER Hypervisor is a basic component of the
system firmware that is layered between the hardware and operating system. POWER
Hypervisor offers the following functions:
򐂰 Provides an abstraction layer between the physical hardware resources and the logical
partitions using them
򐂰
Enforces partition integrity by providing a security layer between logical partitions
򐂰 Controls the dispatch of virtual processors to physical processors and saves and restores
all processor state information during a logical processor context switch
򐂰
Controls hardware I/O interrupt management facilities for logical partitions
򐂰 Provides virtual Ethernet switches between logical partitions that help to reduce the need
for physical Ethernet adapters for interpartition communication
򐂰
Monitors the service processor and performs a reset or reload if it detects the loss of the
service processor, notifying the operating system if the problem is not corrected
򐂰 Uses micro-partitioning to allow multiple instances of the operating system to run on
POWER5, POWER6, and POWER7 processor-based servers and POWER6 and
POWER7 processor-based blades
The POWER Hypervisor is always installed and activated, regardless of system configuration.
The POWER Hypervisor does not own any physical I/O devices; all physical I/O devices in
the system are owned by logical partitions or the Virtual I/O Server.
Memory is required to support the resource assignment to the logical partitions on the server.
The amount of memory required by the POWER Hypervisor firmware varies according to
several factors. The following factors influence POWER Hypervisor memory requirements:
򐂰
Number of logical partitions
򐂰
Number of physical and virtual I/O devices used by the logical partitions
򐂰
Maximum memory values specified in the logical partition profiles
The minimum amount of physical memory to create a partition is the size of the system’s
logical memory block (LMB). The default LMB size varies according to the amount of memory
configured in the system, as shown in Table 3-1 on page 93.
Terminology note: The SDMC, being IBM Systems Director based, uses the term
virtual
server
. This term is used interchangeably with
logical partitions
or
LPARs