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Cc: "Rodney W. Grimes" <freebsd@pdx.rh.cn85.chatusa.com>,
 Juli Mallett <juli@clockworksquid.com>,
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On Nov 5, 2012, at 9:23 AM, Eitan Adler wrote:

> On 4 November 2012 13:28, Rodney W. Grimes
> <freebsd@pdx.rh.cn85.chatusa.com> wrote:
>>=20
>> What ABI is exposing anything about cache parameters or may be come =
dependent
>> on such information?
>=20
> There has been some discussion recently about padding lock mutexs to
> the cache line size in order to avoid false sharing of CPUs. Some have
> claimed to see significant performance increases as a result.

Is that an out-of-kernel interface?

If we did that, we'd have to make it run-time settable, because there's =
no one right answer for arm and MIPS cpus: they are all different.

Warner