Re: Some (small) c++ compilation profiling data (oprofile)

[Karel Gardas <kgardas at objectsecurity dot com>]

On Fri, 17 May 2002, Will Cohen wrote:

> Profiling and characterization of gcc by oprofile would be very useful.
>
> The cvs version of oprofile has a "--reverse" option for oprofpp, which

Thanks, I'll use it in the future reports.

> What environment (hardware and software) did you use to take these
> measurements? Ideally, someone else should be able to reproduce and
> verify the result.  GCC is a moving target, the cvs tag used to check
> out the code should be included. Is the bootstrapped compiler being used
> for the tests? If just the stage1 compiler is being used, the compiler
> used to build the GCC being profiled can influence the measurements.

I've meassured gcc 3.1 (release) bootstraped with standard 3 stage
bootstrap. Since I'm learning oprofile now, I've used standard
configuration and so header of tables look:

Cpu type: CPU with RTC device
Cpu speed was (MHz estimation) : 995.685000
Counter 0 counted RTC_Interrupts events (RTC interrupts/sec (rounded up to power of two)) count 1024
vma      samples  %-age       symbol name
080496f0 0        0           _start
08049714 0        0           Letext

Machine is notebook (apm switched off by 'apm=off' kernel option) 1GHz
PIII 512MB RAM. It seems mobile P6 doesn't provide perf. counter registers
and so oprofile used rtc. I haven't found yet, how to configure oprofile
on my machines to measure other data than time spent in functions.

Cheers,

Karel
--
Karel Gardas                  kgardas@objectsecurity.com
ObjectSecurity Ltd.           http://www.objectsecurity.com