Re: [PATCH tip 0/5] perf: make top share sym routines with report

[Ingo Molnar]

* Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> wrote:

> Haven't done and perf stat runs tho. Perhaps ask for running it 
> for 5 refreshes and then exit.

I've benchmarked it. With about half a million sample IRQs per 
second on a 16way x86 box the overhead went from 22.3%:

   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME   COMMAND          
  4701 mingo     20   0  423m  61m 1796 R 22.3  0.5   0:08.11 perf             

down to:
         
   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME   COMMAND          
  3386 mingo     20   0 88068  61m 1756 R 18.2  0.5   0:03.06 perf      

So it's a ~22% speedup.

Also, there's much less virtual memory used as well - a factor of 5 
reduction (!).

Applied and pushed out - thanks Arnaldo!

	Ingo
--
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/