IBM I5/OS Server User Manual


 
iSeries. mySeries.
Main Storage Concepts
Memory Allocation Facts
Power4 Hypervisor allowed memory manipulation at the single megabyte (1MB) level
Memory in the Power5 machines cannot be manipulated that finely :
Memory must be assigned or moved in blocks
Theses blocks are called “Logical Memory Blocks (LMB)” or “Memory Regions”
About those “Memory Regions” :
LMB are sized in multiples of 16 MB
Future implementations will allow use of 16, 32, 64, 128 or 256 MB blocks
LMB size is a system-wide parameter
LMB is the smallest amount of memory that can be manipulated
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iSeries. mySeries.
Main Storage Concepts
Memory Allocation Facts
Hypervisor uses memory to run the system !
Hypervisor memory used expands and contracts based on many variables :
Number of partitions
Amount of I/O attached to the system
Amount of virtual I/O slots used in each partition
HSL OptiConnect and Virtual OptiConnect links
Starting and/or stopping a partition affects hypervisor memory requirements
Hypervisor memory allocation made by 16 MB increments
Main Storage
P1 P2 P3
Hypervisor HPT1 HPT 2 HPT 3
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