Re: SMP detection

Skylar Thompson wrote:
Michal Mertl wrote:
No! Kernel threads (e.g. handling interrupts) aren't that much different
to normal processes.

Logical CPUs on a single HTT capable CPU share most of the CPU logic,
especially all the external stuff (handling interrupts). Scheduling
handling of interrupts on the "secondary/logical" core wouldn't
probably help performance at all (if that is at all possible).


Could you clarify note 20031022 in /usr/src/UPDATING? It states that HTT
CPUs are used for interrupts if they are detected, even if they aren't
used by regular processes. Was this something that just showed up in
pre-6.x releases?


I think it means that if an interrupt would for some reason be signalled
to the unused logical core it wouldn't be lost or something.

Michal

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