Re: TH1 and Fill

Hello Marc,

Not quite sure about your context. But if you try, for instance, to Fill an histogram using FillRandom(...), most of the time goes actually in TROOT::GetFunction(). About 99% of the time, relative to the context of FillRandom().

So my guess is that the time you are observing goes somewhere else, not in the Fill() itself. Are you using valgrind --tool=callgrind ? ... you can track the callers and see where who is actually spending too much time.

cheers,

John

On Fri, 2010-04-23 at 22:33 +0200, Marc Escalier wrote:
> Dear rooters,
>
> after studying performance from a given program that fill a TH1 histogram
> within a loop on events
>
> loop on the events of the tree
> myhisto->Fill(current event with variable)
>
> i see from a benchmark study that 90 % of the time is consumed by the
> myhisto->Fill(myvariable) command
>
> I was wondering if there are tricks to improve speed of this instruction ?
>
> thank you
>
Received on Fri Apr 23 2010 - 23:05:36 CEST