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Subject: Re: [hwloc-devel] Cache size/sharing errors on 8x4 Opteron system
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2009-09-22 10:44:11


Hello,

Peter Thoman, le Tue 22 Sep 2009 16:36:39 +0200, a écrit :
> However, the L1 cache size is wrong

512K is quite big indeed :)

hwloc gets it from /sys/devices/system/cpu/cpu0/cache/index*/size

> and the L3 cache is in fact shared between each set of 4 cores
> (its size is correct though).

hwloc gets it from /sys/devices/system/cpu/cpu0/cache/index*/shared_cpu_map

I'm afraid the bug is most probably in the kernel, you can send the
result of tests/linux/gather-topology.sh to make sure.

Samuel