Re: Adding several histos

It is likely that your files contain memory resident Trees. Could you send the output of mytree.Print() ? or myfile.ls()

Rene Brun

Manuel Mussini wrote:
>
> Hi all,
>
> I have many files (~70) with the same directories structure and each
> one contains a lot of histograms (~1000).
>
> I always used hadd.C to merge these files but I’ve recently added some
> TH2s (thickly binned) that create a memory problem while merging!
>
> I tried to use the hadd application instead of the script on only 2
> files and it worked fine but the memory was anyway almost filled (I
> don’t know what could happen with 70 files)!
>
> What could be the reason of this high memory usage? Copies of histos
> created during the adding procedure?
>
> Is there a way to workaround the problem?
>
> I have to run it on different machines with different characteristics
> so I’m not interested in the high speed but in the low memory usage!
>
> Thanks a lot for any idea! :-)
>
> Bye…
>
Received on Sun Nov 18 2007 - 16:37:01 CET