perf not measuring LLC events?

perf not measuring LLC events?

[Dervin Thunk]

Dear all,

I'm trying to measure the LLC events of a program. I'm running
linux-tools-3.2.0- 34 on a fairly recent 4 core Intel machine. For a
certain program that reads a 64 MB file into memory, I get

 Performance counter stats for './algo data/E.dna':

                 0 LLC-loads                                                   
                 0 LLC-load-misses
        26,538,349 cache-misses                                                
     4,465,644,541 L1-dcache-misses                                            

      35.116615511 seconds time elapsed

I have tried this in another machine, and it does give me some results
for LLC.  Also Valgrind gives me results (different from 0, that is)

Any idea what I'm doing wrong? Anyone else experiencing this problem
with perf right now? Please let me know if I need to provide more
information.

Thanks.

Re: perf not measuring LLC events?

[Jeff Johnson]

Dervin Thunk <dervin.thunk <at> gmail.com> writes:

> 
> Dear all,
> 
> I'm trying to measure the LLC events of a program. I'm running
> linux-tools-3.2.0- 34 on a fairly recent 4 core Intel machine. For a
> certain program that reads a 64 MB file into memory, I get
> 
>  Performance counter stats for './algo data/E.dna':
> 
>                  0 LLC-loads                                                   
>                  0 LLC-load-misses


Dervin, 
I am experiencing the same issue. I am running perf on an i5 machine. Have you 
gotten any feedback regarding this? 
-Jeff

Re: perf not measuring LLC events?

[Jiri Olsa]

On Fri, Jan 18, 2013 at 04:28:51PM +0000, Jeff Johnson wrote:
> Dervin Thunk <dervin.thunk <at> gmail.com> writes:
> 
> > 
> > Dear all,
> > 
> > I'm trying to measure the LLC events of a program. I'm running
> > linux-tools-3.2.0- 34 on a fairly recent 4 core Intel machine. For a
> > certain program that reads a 64 MB file into memory, I get
> > 
> >  Performance counter stats for './algo data/E.dna':
> > 
> >                  0 LLC-loads                                                   
> >                  0 LLC-load-misses
> 
> 
> Dervin, 
> I am experiencing the same issue. I am running perf on an i5 machine. Have you 
> gotten any feedback regarding this? 

I'm getting some 'sane' numbers on 2 cores i7 SandyBridge on 3.6.11-1.fc17.x86_64

not sure if this was broken back in 3.2.0

please be more specific on what system you're testing on
and provide whole perf stat command line

jirka

Re: perf not measuring LLC events?

[Jeff]

Specs:
i5 Sandy Bridge 2400
Model 42
Stepping 7

Ubuntu 12.10 64 bit.
Dell Optiplex 790


On Mon, Jan 21, 2013 at 6:38 AM, Jiri Olsa <jolsa@redhat.com> wrote:
> On Fri, Jan 18, 2013 at 04:28:51PM +0000, Jeff Johnson wrote:
>> Dervin Thunk <dervin.thunk <at> gmail.com> writes:
>>
>> >
>> > Dear all,
>> >
>> > I'm trying to measure the LLC events of a program. I'm running
>> > linux-tools-3.2.0- 34 on a fairly recent 4 core Intel machine. For a
>> > certain program that reads a 64 MB file into memory, I get
>> >
>> >  Performance counter stats for './algo data/E.dna':
>> >
>> >                  0 LLC-loads
>> >                  0 LLC-load-misses
>>
>>
>> Dervin,
>> I am experiencing the same issue. I am running perf on an i5 machine. Have you
>> gotten any feedback regarding this?
>
> I'm getting some 'sane' numbers on 2 cores i7 SandyBridge on 3.6.11-1.fc17.x86_64
>
> not sure if this was broken back in 3.2.0
>
> please be more specific on what system you're testing on
> and provide whole perf stat command line
>
> jirka

Specs:
i5 Sandy Bridge 2400
Model 42
Stepping 7

Ubuntu 12.10 64 bit.
Dell Optiplex 790

Perf command: perf stat -e LLC-loads -r 3 <my binary under test>

Thanks,
Jeff

Re: perf not measuring LLC events?

[Jiri Olsa]

On Mon, Jan 21, 2013 at 08:10:03AM -0800, Jeff wrote:
> Specs:
> i5 Sandy Bridge 2400
> Model 42
> Stepping 7
> 
> Ubuntu 12.10 64 bit.
> Dell Optiplex 790
> 
> 
> On Mon, Jan 21, 2013 at 6:38 AM, Jiri Olsa <jolsa@redhat.com> wrote:
> > On Fri, Jan 18, 2013 at 04:28:51PM +0000, Jeff Johnson wrote:
> >> Dervin Thunk <dervin.thunk <at> gmail.com> writes:
> >>
> >> >
> >> > Dear all,
> >> >
> >> > I'm trying to measure the LLC events of a program. I'm running
> >> > linux-tools-3.2.0- 34 on a fairly recent 4 core Intel machine. For a
> >> > certain program that reads a 64 MB file into memory, I get
> >> >
> >> >  Performance counter stats for './algo data/E.dna':
> >> >
> >> >                  0 LLC-loads
> >> >                  0 LLC-load-misses
> >>
> >>
> >> Dervin,
> >> I am experiencing the same issue. I am running perf on an i5 machine. Have you
> >> gotten any feedback regarding this?
> >
> > I'm getting some 'sane' numbers on 2 cores i7 SandyBridge on 3.6.11-1.fc17.x86_64
> >
> > not sure if this was broken back in 3.2.0
> >
> > please be more specific on what system you're testing on
> > and provide whole perf stat command line
> >
> > jirka
> 
> Specs:
> i5 Sandy Bridge 2400
> Model 42
> Stepping 7
> 
> Ubuntu 12.10 64 bit.
> Dell Optiplex 790
> 
> Perf command: perf stat -e LLC-loads -r 3 <my binary under test>

I found Ubuntu 12.10 is like 3.5 kernel, right?

There are some perf tool cache event fixies after 3.5,
but non of the tags I tried showed the error.

Any chance you could try with latest upstream - kernel/perf?

jirka