Re: Perf 2.6.32-220.el6.x86_64 problem when recording 2 counters

[David Ahern <dsahern@gmail.com>]

On 5/24/12 1:14 AM, HUMMEL Michel wrote:
> I've written the test to run bad_perfo first, and then good_perfo and now only bad_perfo is in the report :
>
> $ perf record -e  cycles,instructions  -o perf.data.cycles.instructions2 ./test_perfo2
> $ perf report -i perf.data.cycles.instructions2 --stdio
> # Events: 8K cycles
> #
> # Overhead  Command      Shared Object                     Symbol
> # ........  .......  .................  .........................
> #
>      99.52%  test_perfo2  test_perfo2        [.] bad_perfo
>       0.06%  test_perfo2  [kernel.kallsyms]  [k] copy_page_c
>       0.05%  test_perfo2  [kernel.kallsyms]  [k] apic_timer_interrupt
>       0.04%  test_perfo2  [kernel.kallsyms]  [k] run_timer_softirq
>
>
> # Events: 8K instructions
> #
> # Overhead  Command      Shared Object                   Symbol
> # ........  .......  .................  .......................
> #
>      99.82%  test_perfo2  test_perfo2        [.] bad_perfo
>       0.04%  test_perfo2  ld-2.12.so         [.] _dl_lookup_symbol_x
>       0.01%  test_perfo2  [kernel.kallsyms]  [k] clear_page_c
>       0.01%  test_perfo2  [kernel.kallsyms]  [k] update_wall_time
>

Can you try an upstream version of the perf binary? It should be able to 
read the data file. You can use the perf-script command to dump the 
events and look at what was recorded and which type of event (cycles vs 
instructions). Adding -R to the record will get the timestamp added to 
each sample and look at the delta time between samples. Maybe that will 
give a clue.

David