Re: perf tools miscellaneous questions

From: Francis Moreau
Date: Sat Nov 06 2010 - 10:44:36 EST


Vince Weaver <vweaver1@xxxxxxxxxxxx> writes:

> On Fri, 5 Nov 2010, Francis Moreau wrote:
>
>> Victor Jimenez <victor.javier@xxxxxx> writes:
>>
>> [...]
>>
>> > If you are measuring last level cache misses, I would recommend you to
>> > use a memory intensive application/benchmark instead of /bin/true, as
>> > otherwise there can be a significant variation between two runs.
>>
>> I agree.
>>
>> But still with intensive application, I got the same results:
>
>
> you're going to need to get your architectural manual for your processor
> and use raw events (not the kernel default ones) if you really want to
> find out what's going on. A tool like libpfm4 can help change the names
> to raw events for you.

Ouch that's a bit rude for a man page ;)

Specially since 'llc-loads-misses' is and should be self speaking.

OK, my cpu is described by:

,----
| vendor_id : GenuineIntel
| cpu family : 6
| model : 15
| model name : Intel(R) Core(TM)2 CPU T5500 @ 1.66GHz
`----

Could you point out the best architecture manual for it which describe
the raw events ?

BTW, I'm wondering if event names are coherent across the different
architectures supported by Linux.

Thanks
--
Francis
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/