[[asc:workbook| <<back]]
====== Working with PROOF ======

You can use PROOF on the cluster. It is advised to use 6-7 cores when using PROOF line (since we have 8 physical cores per server).

You can find some ATLAS instructions here:

https://twiki.cern.ch/twiki/bin/viewauth/AtlasProtected/PhysicsAnalysisWorkBookRel16D3PDAnalysisExample

https://twiki.cern.ch/twiki/bin/viewauth/AtlasProtected/PhysicsAnalysisWorkBookPROOF

There is an example in

/users/chakanau/public/proof/

(kindly provided by Duong Nguyen)

How  it works:
<code>
cd Ana_proof
./RootCore/configure
source RootCore/scripts/setup.sh
RootCore/scripts/find_packages.sh
RootCore/scripts/clean.sh
RootCore/scripts/compile.sh
python runSkimAna.py
</code>

First, we compile RootCore libraries. Then we run "runSkimAna.py". The actual C++ program is runRootCore.C
There are proof or non-proof option at line 55, 56 in runSkimAna.py.


===== Jet example =====

A typical example to work with jets is 

/users/chakanau/public/proof/jets

Compile the code "make" and run A_RUN_TEST.

The main code is "main.cxx" where you can say tell yes" to the prooflite option. We fill jet histograms in src/Jets.cxx" (the event loop).
src/Truth.cxx - keep track the truth info.
Histogram are defined in inc/Ana.h and src/IniHistograms.cxx. The output is in out/output.root.