xAOD::TFileAccessTracer Class Reference

#include <TFileAccessTracer.h>

List of all members.

Classes
class	AccessedFile
	Helper class storing information about the accessed files.
Public Member Functions
	TFileAccessTracer ()
	Default constructor.
	~TFileAccessTracer ()
	Destructor.
void	add (const ::TFile &file)
	Add information about a new file that got accessed.
const std::string &	serverAddress () const
	The address of the server that information is sent to.
void	setServerAddress (const std::string &addr)
	Set the address of the server that information is sent to.
::Double_t	monitoredFraction () const
	Fraction of jobs that should send monitoring information.
void	setMonitoredFraction (::Double_t value)
	Set the fraction of jobs that should send monitoring information.
Static Public Member Functions
static void	enableDataSubmission (::Bool_t value)
	Function for turning data submission on/off.

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Detailed Description

Helper class keeping track of the files that got accessed

This class helps in keeping track of which files get accessed during a job. To be able to report about them to the DDM (Rucio) system in a way that doesn't rely on the grid middleware. (So backdoor access to files stored at data centres becomes visible to the DDM system.)

The class can also send information about which branches/variables got accessed in the job. This it simply gets from the xAODCore code.

xAOD::TEvent uses this class to send information about xAOD access to the central Rucio monitoring infrastructure. This default behaviour can be influenced in two ways:

• Use the TFileAccessTrancer::enableDataSubmission function to disable data submission from a particular application;
• Set the environment variable "XAOD_ACCESSTRACER_FRACTION" to a floating point value, which is the fraction of jobs that should be monitored within that session. This is mostly for grid purposes...

Author:

Attila Krasznahorkay <Attila.Krasznahorkay@cern.ch>

Revision

781356

Date

2016-10-31 15:03:28 +0100 (Mon, 31 Oct 2016)

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Constructor & Destructor Documentation

xAOD::TFileAccessTracer::~TFileAccessTracer

(

)

Destructor.

The destructor of the class is the one doing most of the heavy lifting. If the $SEND_XAOD_FILE_ACCESS_STAT environment variable is set when the object gets deleted, it posts all the information it collected, to the address defined by SERVER_ADDRESS. By constructing an HTTP message from scratch.

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Member Function Documentation

void xAOD::TFileAccessTracer::add

(

const ::TFile &

file

)

Add information about a new file that got accessed.

This function is called by TEvent to record which files were read from during the job.

Parameters:

file

The file object that is being read from

void xAOD::TFileAccessTracer::enableDataSubmission

(

::Bool_t

value

)

[static]

Function for turning data submission on/off.

This function can be used by concerned users to turn off data collection and submission for their jobs completely.

Parameters:

value

Setting whether data submission should be enabled or not

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The documentation for this class was generated from the following files:

• /cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.28/xAODRootAccess/xAODRootAccess/tools/TFileAccessTracer.h
• /cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.28/xAODRootAccess/Root/TFileAccessTracer.cxx