Hitachi Compute Blade 2000 User Manual page 1071

The memory access cost from the processor in Node0 to the memory in Node3 is larger
than the access cost to the memory in Node1, since it is necessary to go through Node1
to access memory in Node3.
Physical
memory
Physical
processor
Physical
processor
Physical
memory
For Processor 0, the memory in Node 0 is local memory, the
memory in Node1, Node2 or Node3 is remote memory.
Memory accesses on the NUMA configuration
(in the case of four nodes)
In the server blade, which is set to non-NUMA, memory is automatically interleaved and
any programs do not need to access the memory, the memory access performance to
all the memory area becomes middle of the memory access performance of local
memory and remote memory.
Physical Processor 0
processor
Physical
memory
Node0
Memory accesses on the Non-NUMA configuration
Node0 Node1
small
large
Processor 0
Processor 1
large
Processor 2 Processor 3
Node2 Node3
Processor 1
Node1
1020
Memory access
Memory
access cost
Interconnect
Memory access
Memory
access cost
Interconnect
Memory access is
dispersed
Interleaved
Memory of (Non-NUMA)