IBM BladeCenter PS703, Technical Overview And Introduction

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IBM BladeCenter PS703 and PS704 Technical Overview and Introduction
increase system use without compromising the computing power for critical workloads in a
dedicated processor.
Figure 3-5 shows how the dedicated shared processor mode can be configured.
Figure 3-5 IVM console shows how to configure dedicated shared processor
Shared mode
In shared mode, logical partitions use virtual processors to access fractions of physical
processors. Shared partitions can define any number of virtual processors (maximum number
is 10 times the number of processing units assigned to the partition). From the POWER
Hypervisor perspective, virtual processors represent dispatching objects. The POWER
Hypervisor dispatches virtual processors to physical processors according to a partition’s
processing units entitlement. One processing unit represents one physical processor’s
processing capacity. At the end of the POWER Hypervisor’s dispatch cycle (10 ms), all
partitions receive total CPU time equal to their processing units entitlement. The logical
processors are defined on top of virtual processors. Therefore, even with a virtual processor,
the concept of logical processors exists and the number of logical processors depends on
whether the simultaneous multithreading is turned on or off.
3.4.3 Multiple Shared-Processor Pools
One of the functions now available on POWER6- and POWER7-based blades managed by
an SDMC is Multiple Shared-Processor Pools (MSPPs). This capability allows a system
administrator to create a set of micro-partitions with the purpose of controlling the processor
capacity that can be consumed from the physical shared-processor pool.
To implement MSPPs, there is a set of underlying techniques and technologies. An overview
of the architecture of Multiple Shared-Processor Pools can be seen in Figure 3-6.