People here seem to presume that all the world SMPs are UMA systems.
Taxonomy of parallel computers (by David Black, back then at CMU):
- UMA Uniform Memory Access (your usual tightly coupled SMP)
- NUMA Non-Uniform Memory Access (processors have good access
to memory which is local to them, but slower access to
memory at other CPU/MEM boards; beasts like SUN E 10000)
- NORMA NO Remote Memory Access (your average Beowulf)
Spice this with Cache Coherence, and you get CC-NUMA (and CC-UMA).
(That was after "In Search of Clusters" by Gregory F. Pfister)
Your observations may well hold at UMA systems.
Binding facilities make a *lot* sense at NUMA systems.
(Also memory allocation policies must be tuned accordingly; allocing
process local memory from remote board hurts process, AND system
performance when processor most go thru system memory crossbar to
access that memory causing contention for that resource..)
/Matti Aarnio <matti.aarnio@sonera.fi>
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