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Subject: Re: [hwloc-devel] Strange results on itanium 2
From: Brice Goglin (Brice.Goglin_at_[hidden])
Date: 2010-10-31 04:45:04


Le 30/10/2010 00:55, Jirka Hladky a écrit :
>
> > >> L2 and one L1 per core. Your machine has hyperthreading, so our
>
> > >> This work-around worked fine on old itaniums since they had one
> L3, one
>
> > >> work-around creates one L3 per thread, while L1 and L2 (properly
>
> > >> reported by the kernel) are core-specific. Maybe hwloc should just
>
> > >> ignore caches with invalid shared_cpu_map.
>
>
> BTW, it's Intel Itanium2 9140N CPU with 18MB of L3 cache.
>

It looks all Itaniums (even the latest 93xx ones) have per-core L1/L2/L3
caches. Nothing is ever shared between cores. So a best workaround would
be to use the core cpuset (both threads) when the cache cpuset is wrong
(instead of using the thread cpuset like we do right now). I'll likely
commit that later.

Brice