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Subject: Re: [hwloc-devel] hwloc powerpc rhel5 and power7 patch
From: Alexey Kardashevskiy (aik_at_[hidden])
Date: 2010-09-16 01:42:27


Please find the answers below.

On 16/09/10 15:29, Samuel Thibault wrote:
> Alexey Kardashevskiy, le Thu 16 Sep 2010 14:10:08 +1000, a écrit :
>
>> 1. Old kernels (RHEL5.*) do expose some numa nodes via sysfs but there
>> is no information regarting cache (L1/L2/L3) and CPU threads. RHEL6 does
>> that. The proposed patch parses PowerPC's /proc/device-tree and add
>> necessary information into the topology.
>>
> Mmm, is that information not available on RHEL6 through the standard
> /sys/devices/system/cpu/cpu*/cache too?
>

It is available on RHEL6 and not available on RHEL5. So the patched code
looks to sysfs first and if there were no cache info found, goes to the
device-tree. Workaround, yes.

> Could you post a tgz output example of tests/linux/gather-topology.sh on
> RHEL6 so we can include a testcase for your code?
>

Attached, both files.