Re: Problem using CopyTree

The original message
  " Fatal in <TStorage::ReAllocChar>: storage exhausted" should be clear. Your ntuple with 6 miliion entries occupies 240 Mbytes in memory. Depending on your selection, you may end up with 480 Mbytes in memory. How much memory do you have on your machine? Send the shortest possible script reproducing your problem in case you cannot find another solution.

Rene Brun

On
Fri, 27 May
2005, Woon-Seng Choong wrote:

> Rene,
> I didn't even create a TFile object because I just filled the ntuple and
> process the ntuple in the same program without having the intention to save
> the ntuple. I did what you suggested by creating the TFile object before I
> create the ntuple. But I am still getting the same error when I called
> CopyTree. What is the limitation of using memory-resident ntuples. Why is it
> necessary to create a TFile object in relation to CopyTree?
>
> Thank you
> Seng
>
>
> On May 27, 2005, at 1:19 AM, Rene Brun wrote:
>
>> Hi Seng,
>>
>> It seems that you are creating memory-resident ntuples.
>> To create disk-resident ntuples, do
>> TFile *f = new TFile("myfile.root","recreate");
>> TTree *T = new TNtupleD(...
>>
>> and not
>> TTree *T = new TNtupleD(...
>> TFile *f = new TFile("myfile.root","recreate");
>>
>> Rene Brun
>>
>> On Thu, 26 May 2005, Woon-Seng Choong wrote:
>>
>>> Hi,
>>> I am running root version 4.04.00 on a Window 2000 platform. I have an
>>> object of class NtupleD which has 5 elements in it. The object has
>>> slightly over 6 milllion events. I tried to use CopyTree with selection
>>> to prefilter the ntuple for further processing. But I got the following
>>> error messages from root:
>>>
>>> Fatal in <TStorage::ReAllocChar>: storage exhausted
>>> aborting
>>> Warning in <TWinNTSystem::StackTrace>: this method must be overridden!
>>>
>>> This application has requested the Runtime to terminate it in an unusual
>>> way.
>>> Please contact the application's support team for more information.
>>>
>>>
>>> Can someone help me? Thanks.
>>>
>>> Seng
>>>
>>>
>
Received on Sat May 28 2005 - 09:02:31 MEST