"Yousuf Khan" wrote in message
gers.com...
I just remembered that pretty soon there will be dual-core Opterons too,
so
that in itself will add another level of NUMA to take into account.
Internal
chip-connect vs. Hypertransport connect vs. customized board-to-board
connect.

Does an OS really need to be aware of the difference between two cores on
the same chip?

Linux has a concept of a NUMA "node", where all of the processors in a node
are considered equivalent. It'll still try to schedule threads on the same
CPU they last ran on, but next it will try other CPUs in the same node
before giving up and sending it to any available node.

IIRC, the code already understands two-CPU nodes, because that is how
Intel's SMT chips are handled. Treating K8 CMP the same way sounds correct,
once AMD releases specs on how to recognize dual-core chips.

S

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Stephen Sprunk "Those people who think they know everything
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