IBM I5 Server User Manual


 
iSeries. mySeries.
Processor Concepts
Virtual Processors
Rules & requirements :
It is possible to allocate more virtual processors than there are in the shared processor pool
The actual number of processor in the shared processor pool is a “floating” number
A single physical processor can report in the system as a n-ways
You cannot allocate less than 0.10 PU per virtual processor
Example : requesting 0.20 PU to run on 4 VCPU means 0.20 / 4 = 0.05 < 0.10 !
Changes are dynamic, without any IPL within the configured ranges
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iSeries. mySeries.
Processor Concepts
Uncapped Processors
Uncapped allows to potentially utilizes unused processor capacity in the system
Uncapped weight is used to determine how unused capacity is distributed :
P1 weight is 200
P2 weight is 100
P1 will receive 2/3 of the unused shared processor capacity
P2 will receive 1/3 of the unused shared processor capacity
If P1 does not need all 2/3 of capacity, then P2 could get more !
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