Re: opcontrol does not create results

Hi Bernd,

it's possible to dive deeply. You need to have debuginfo for all the things
you want to dive in, so in this case for kernel. When you have debuginfos,
you may run:

opreport -wl
--> that should give you information of samples per process/function

opreport -d
--> that should go per address/instruction

opreport -gl
--> if you have proper debuginfo, you can see line numbers etc.

You may be also interested in generating a callgraph, but for that you need
to run your measurement with "-c" and then you may run "opreport -c". But
it's pretty possible, that your kernel doesn't support that or it doesn't
have it enabled.

Another interesting thing is the opannotate tool, which reads the sources
and creates a copy of your source tree, where the source files are annotated
by samples per line. That's awesome for user space profiling, but in case
of kernel it would be probably an overkill...

Note: If you install some additional debuginfos, you would probably need
to re-run all the measurements to get the results!

Last thing is that I'd recommend you to run the measurement for longer time.
Your example report doesn't contain that many samples, you may need more for
the investigation.

Regards,
Michael


----- Mensaje original -----
> De: "Bernd Lentes" <[email protected]>
> Para: "Michael Petlan" <[email protected]>
> CC: [email protected]
> Enviados: Jueves, 12 de Marzo 2015 18:56:55
> Asunto: RE: opcontrol does not create results
> 
> Hi Michael,
> 
> thanks for providing me with this information. I made one step ahead.
> This is my result:
> 
> idcc-devel:~ # /usr/bin/opreport
> CPU: CPU with timer interrupt, speed 0 MHz (estimated)
> Profiling through timer interrupt
>           TIMER:0|
>   samples|      %|
> ------------------
>      4901 98.0396 vmlinux-2.6.16.60-0.103.1-smp.gz
>        40  0.8002 atop
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                22 55.0000 libz.so.1.2.3
>                15 37.5000 vmlinux-2.6.16.60-0.103.1-smp.gz
>                 2  5.0000 libc-2.4.so
>                 1  2.5000 jbd
>        35  0.7001 sshd
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                35 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
>        12  0.2400 bash
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                10 83.3333 vmlinux-2.6.16.60-0.103.1-smp.gz
>                 1  8.3333 bash
>                 1  8.3333 libc-2.4.so
>         2  0.0400 ls
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 2 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
>         2  0.0400 klogd
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 2 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
>         1  0.0200 cat
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 1 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
>         1  0.0200 grep
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 1 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
>         1  0.0200 rm
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 1 100.000 jbd
>         1  0.0200 ext3
>         1  0.0200 expr
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 1 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
>         1  0.0200 oprofiled
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 1 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
>         1  0.0200 hald-addon-storage
>                   TIMER:0|
>           samples|      %|
>         ------------------
>                 1 100.000 vmlinux-2.6.16.60-0.103.1-smp.gz
> idcc-devel:~ #
> 
> It shows that most of the time is used by the kernel. This is not surprising.
> But what is the kernel exactly doing ?
> How can I achieve more information about that ?
> 
> Bernd
> 
> 

------------------------------------------------------------------------------
Dive into the World of Parallel Programming The Go Parallel Website, sponsored
by Intel and developed in partnership with Slashdot Media, is your hub for all
things parallel software development, from weekly thought leadership blogs to
news, videos, case studies, tutorials and more. Take a look and join the 
conversation now. http://goparallel.sourceforge.net/