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Subject: Re: [hwloc-users] hwloc 0.9.3 not showing opt275 caches correctly?
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2010-01-23 14:22:17


Hello,

Brock Palen, le Sat 23 Jan 2010 13:51:09 -0500, a écrit :
> System(7870MB)
> Node#0(3906MB) + Socket#0
> L2(1024KB) + L1(1024KB) + Core#0 + P#0
> L2(1024KB) + L1(1024KB) + Core#1 + P#1
> Node#1(4040MB) + Socket#1
> L2(1024KB) + L1(1024KB) + Core#0 + P#2
> L2(1024KB) + L1(1024KB) + Core#1 + P#3
>
> If I am reading the AMD docs right, the L1 cache for each core should
> be smaller, and in two parts, (data and instruction cache)
> Also appears that L2 should be shared, as far as I can tell, it is not
> shared in this case.
>
> Am I looking at this wrong?

No, that's the right interpretation of lstopo's output.

However, the bug probably lies into your kernel's code. Could you check

/sys/devices/system/cpu/cpu*/cache/index*/size

?

Samuel