Micro-Partitioning

Micro-Partitioning, also known as shared processor partitioning, is a form of logical partitioning which was introduced by IBM on systems using the POWER5 processor. It only differs from a dedicated processor partition in the way CPU utilization is configured and managed by the POWER Hypervisor (PHYP) firmware. All IBM POWER5 and POWER6 systems are partitioned and will run "on top" of the PHYP. The POWER Hypervisor controls time slicing, management of all hardware interrupts, dynamic movement of resources across multiple operating systems, and dispatching of logical partition workloads. When a shared processor partition is activated by the PHYP, the logical partition (LPAR) is guaranteed a certain processing capacity, if needed, and a number of virtual processors, based on configuration and current availability. The processing capacity is drawn from a pool of shared processor resources. The minimum processing capacity per processor is 1/10 of a physical processor core, with a further granularity of 1/100. The PHYP uses a 10 ms time slicing dispatch window for scheduling all shared processor partitions' virtual processor queues to the PHYP physical processor core queues. A shared processor partition can be either capped or uncapped. A capped partition can never exceed the currently configured processing capacity, whereas an uncapped partition can exceed the currently configured processing capacity up to 100% of the number of the currently configured virtual processors. If the shared processor partition is DLPAR capable, the number of virtual processors and processing capacity can be altered dynamically for the partition.

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Micro-Partitioning, also known as shared processor partitioning,^[1] is a form of logical partitioning which was introduced by IBM on systems using the POWER5 processor. It only differs from a dedicated processor partition in the way CPU utilization is configured and managed by the POWER Hypervisor (PHYP) firmware.^[2] All IBM POWER5 and POWER6 systems are partitioned and will run "on top" of the PHYP.^[3]

The POWER Hypervisor controls time slicing, management of all hardware interrupts, dynamic movement of resources across multiple operating systems, and dispatching of logical partition workloads.

When a shared processor partition is activated by the PHYP, the logical partition (LPAR) is guaranteed a certain processing capacity, if needed, and a number of virtual processors, based on configuration and current availability. The processing capacity is drawn from a pool of shared processor resources.^[4]: 6

The minimum processing capacity per processor is 1/10 of a physical processor core, with a further granularity of 1/100.^[5][6][7] The PHYP uses a 10 ms time slicing dispatch window for scheduling all shared processor partitions' virtual processor queues to the PHYP physical processor core queues. A shared processor partition can be either capped or uncapped. A capped partition can never exceed the currently configured processing capacity, whereas an uncapped partition can exceed the currently configured processing capacity up to 100% of the number of the currently configured virtual processors.^[4]: 10

If the shared processor partition is DLPAR capable, the number of virtual processors and processing capacity can be altered dynamically for the partition.^[4]: 9

References

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1. ^ Chen, Whei-Jen; Jason Chan; Olaf Mueller; Malcolm Singh; Tapio Väättänen (2009). DB2 Virtualization. IBM Redbooks. p. 49. ISBN 9780738433431 – via Google Books.
2. ^ Williams, David E. (2007). Virtualization with Xen. Elsevier. pp. 7–8. ISBN 9780080553931 – via Google Books.
3. ^ Victor, Jeff; Jeff Savit; Gary Combs; Simon Hayler; Bob Netherton (2011). Oracle Solaris 10 System Virtualization Essentials. Prentice-Hall. p. 34. ISBN 013708188X – via Google Books.
4. ^ ^{a b c} Gibson, Chris (July 2007). "Implementing Micro-Partitioning on the IBM p5 595 Server". Sys Admin. Vol. 16, no. 15. CMP Media. pp. 6–16 – via Google Books.
5. ^ Mears, Jennifer (May 3, 2004). "IBM powers up server partitioning". Network World. Vol. 21, no. 18. IDG Publications. p. 8. ProQuest 215966612.
6. ^ Langley, Nick (March 28, 2006). "AIX celebrates 20th anniversary and forges ahead alongside Linux". Computer Weekly. Reed Business Information. p. 50. ProQuest 237027130 – via ProQuest.
7. ^ Akin, David (July 15, 2004). "IBM to launch servers offering more power for a lot less cash". The Globe and Mail. Bell Globemedia. p. B11 – via ProQuest.

See also

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• VM (operating system)

External links

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• IBM System p Virtualization — The most complete virtualization offering for UNIX and Linux
• System i and System p: Introduction to Virtualization^{[permanent dead link]}
• System i and System p: Advanced POWER Virtualization Operations Guide^{[permanent dead link]}
• System i and System p: Logical Partitioning Guide^{[permanent dead link]}
• Advanced POWER Virtualization on IBM System p5: Introduction and Configuration
• IBM System p Advanced POWER Virtualization Best Practices
• Partitioning Implementations for IBM eServer p5 Servers, SG24-7039
• POWER5 Hypervisor
• Virtualization Concepts
• Virtualization in System p
• POWER5 Hypervisor