Using the BNL PROOF Test Bed

Introduction

What is PROOF?

What can I use PROOF for?

What is the BNL PROOF Test Bed?

Getting Started with PROOF at BNL

Right now the test bed has restricted access. If you would like to try this, contact Sergey at panitkin@bnl.gov to add your BNL account name to the list. If you would like to try to run PROOF locally instead of at BNL, follow the xproofd setup instructions on the ROOT website (NOTE: in order to run xrootd, you need to setup ROOT).

Check out the Getting Started package

First setup CVSROOT; e.g., setenv CVSROOT /afs/usatlas.bnl.gov/software/cvs for tcsh at BNL

Check out the PROOF package:

cvs co -d PROOF groups/PROOF

Notice that under PROOF, there are 2 directories: ARA-PROOF_BNL and ProofNtupleAnalysis. The directory ARA-PROOF_BNL contains examples for running PROOF with AthenaROOTAccess (both in python and CINT), and the directory ProofNtupleAnalysis contains an example for running PROOF over a standard ROOT ntuple.

Run a Very Simple Example

In this example, you will open a PROOF session, add a file to a TChain, and Draw() a simple quantity.

cd PROOF/ProofNtupleAnalysis

source SetupROOTforPROOF.csh

root

TProof::Open("acas0420");

TChain *ch = new TChain("FullRec0");

ch->Add("/usatlas/workarea/yesw2000/root/Data/HPTV/user.TARRADEFabien.trig1_misal1_csc11.005145.PythiaZmumu.Athena_12.0.6.GroupArea_12.0.6.6.Jamboree_II-HightPtView-00-00-30.AAN.AANT3._00010.root");

ch->SetProof(kTRUE,kTRUE);

TStopwatch t;
t.Start();
ch->Draw("Jet_C4_p_T","Jet_C4_N>0");
t.Stop();
t.Print();

The output should look something like this:

Reset Your PROOF Session

Sometimes your PROOF session will get corrupted and TProof::Open() will hang. Reset your session to restore functionality:

 TProof::Reset("acas0420");

Find Available Data

You can use dq2_ls to see the datasets on the xrootd server:

dq2_ls -fp -s BNLXRDHDD1 "my_dataset" > file_list.txt

You need to use the physical filename (-p option). If you would like a dataset to be copied over to the xrootd server, contact Sergey at panitkin@bnl.gov. Alternatively, you can access data on NFS at BNL by providing the full path name.

Examples

NOTE: This section is under construction

Examples that show you how to use PROOF:

• Using TSelector to analyze an ntuple / tertiary DPD
• Using AthenaROOTAccess to analyze an AOD
• Using PyROOT
• Using TPySelector?
• Using DQ2IF to add files in a DQ2 dataset to a TDSet or TChain

Additional Useful Links

• From the BNL Jamboree, June 2008: Sergey's talk, Shuwei's talk