GLAST Ground Software CHEP 2007, Victoria, Daniel Flath 1 The GLAST Data Handling Pipeline...

GLAST Ground Software

CHEP 2007, Victoria, Daniel Flath 1

The GLAST Data The GLAST Data Handling PipelineHandling Pipeline

““Pipeline II”Pipeline II”

Daniel Flath for the GLAST CollaborationStanford Linear Accelerator Center

Gamma-ray Large Gamma-ray Large Area Space Area Space TelescopeTelescope



OutlineOutline

Introduction to GLAST

Computing and GLAST

Pipeline Components

Processing Task Examples

Conclusion



GLAST Key FeaturesGLAST Key Features

• Huge field of view– LAT: 20% of the sky at any instant; in sky survey mode, expose all parts of sky for

~30 minutes every 3 hours. GBM: whole unocculted sky at any time.• Huge energy range, including band 10 GeV - 100 GeV• Will transform the HE gamma-ray catalog:

– by > order of magnitude in # point sources– spatially extended sources– sub-arcmin localizations (source-dependent)

Large Area Telescope (LAT)

GLAST Burst Monitor (GBM)

spacecraft partner: General Dynamics

Two GLAST instruments:LAT: 20 MeV – >300 GeVGBM: 10 keV – 25 MeV

Launch: Feb 5, 2008. Cape Kennedy 565 km, circular orbit 5-year mission (10-year goal)



GN

HEASARCGSFC

DELTA7920H

White Sands

TDRSS SNS & Ku

LAT Instrument Science

Operations Center

GBM Instrument Operations Center

GRB Coordinates Network

Telemetry 1 kbps

AlertsData, Command Loads

Schedules

Schedules

Mission Operations Center (MOC)

GLAST Science Support Center

GLAST Spacecraft

Large Area Telescope& GBM

GPS

GLAST MISSION ELEMENTS



e+ e–

Overview of LATOverview of LAT

• Precision Si-strip Tracker (TKR) 18 XY tracking planes. Single-sided silicon strip detectors (228 m pitch) Measure the photon direction; gamma ID.

• Hodoscopic CsI Calorimeter (CAL)Array of 1536 CsI(Tl) crystals in 8 layers. Measure the photon energy; image the shower.

• Segmented Anticoincidence Detector (ACD) 89 plastic scintillator tiles. Reject background of charged cosmic rays; segmentation removes self-veto effects at high energy.

• Electronics System Includes flexible, robust hardware trigger and software filters.

Systems work together to identify and measure the flux of cosmic gamma Systems work together to identify and measure the flux of cosmic gamma rays with energy 20 MeV - >300 GeV.rays with energy 20 MeV - >300 GeV.

Calorimeter

Tracker

ACD [surrounds 4x4 array of TKR towers]



Motivation: General Computing RequirementsMotivation: General Computing Requirements

• Data rate:– 400Hz total (5Hz Signal)– 12GB raw data, total, over 8 daily downlinks

• Prompt Processing:– Reconstruct downlink within 1hr of receipt– Provide results to collaboration, other missions for:

• Analysis, Monitoring • Flaring, bursting source detection• Follow-up observation, confirmation

– Result: 500GB reconstructed data per day

• Monte Carlo:– Ongoing throughout mission, ~100TB/yr



SLAC

SLAC

Pipeline ComponentsPipeline Components

PipelineServer

OraclePipeline Web Interface

Line ModeClient

Catalog WebInterface

IN2P3Job Control

BatchFarm

INFNJob Control

BatchFarm

Data Portal

CommandClient

Data Catalog

Oracle

SLACJob Control

BatchFarm

Client

Client

Client

ClientClient

Client

Client

read-only

read-only



Example: A “Simple” TaskExample: A “Simple” Task

getIntervalData

diffuseResponses liveTimeCube

launchRoiAnalysis

DRP_monitoring

roiAnalysisgetRoiData

exposureMap

combineExpMaps

sourceAnalysis

launchEnergyBandAnalysis

fitEnergyBand

energyBandAnalysis

fitEnergyBand

energyBandAnalysis

roiAnalysisgetRoiData

exposureMap

combineExpMaps

sourceAnalysis

launchEnergyBandAnalysis

drpExpMap

exposureSubMap

drpExpMap

exposureSubMap

drpExpMap

exposureSubMap

drpExpMap

exposureSubMap

Script Process Jython; Runs as thread inside Server Process. Launches Subtasks, sets variables, registers datasets with Data Catalog

SubTask Provides parallelism

Execution Condition

Batch Process Compute intensive: Dispatched to farm. Results collected via email.

Success, Failure, (all)-Completed

Sub-SubTask



The Real Deal: Downlink Prompt ProcessingThe Real Deal: Downlink Prompt Processing

Reconstruction

DigitizationM

erge

Merge

Reg

iste

r

Verify

Clean

Calibration

Monitoring



Usage Plots: Activity SummaryUsage Plots: Activity Summary



Usage Plots: Task Activity DetailUsage Plots: Task Activity Detail



Processing Plots: Single Process StatisticsProcessing Plots: Single Process Statistics

Maintain a record of:

•Total time (Wall Clock)

•Wait (Pending) time

•CPU time used

•Node name (machine class)

Expect this to be ~1.0 if our process is not I/O bound

CPU Factors show up



Pipeline Front End: Stream ViewPipeline Front End: Stream View



Technologies UsedTechnologies Used

• Database– Oracle– Java (and PL/SQL) Stored Procedures

• Servers and Client Libraries (Pipeline, Data Catalog)– Java

• Web:– Apache/Tomcat servers– JSP for web pages

• DisplayTag for tabular data• AIDA TLD for plotting• Custom TLDs expose Pipeline client methods

– Java Servlets• Serve GraphViz State diagrams



ConclusionConclusion

• Pipeline is currently in extensive use:– Monte Carlo Production – Integration and Test

• raw data processing• monitoring

• Software not coupled specifically to GLAST or SLAC– Could be used elsewhere– Additional batch farms incorporated by implementing simple Job

Control (Java)-Interface– Contact <[email protected]> if you are interested

• To see GLAST Pipeline II, Data Catalog (and much more!) in action:– http://glast-ground.slac.stanford.edu

• For more on DisplayTag (plotting in web pages):– Victor Serbo: “JAIDA, JAS3, WIRED4 and the AIDA tag library” --

EP7, Carson Hall A, Thursday August 6 17:30



AcknowledgmentsAcknowledgments

Software Development Team:Daniel FlathCharlotte HeeKaren HeidenreichTony JohnsonIgor PavlinMax Turri

Brave Users:Warren FockeTom Glanzman



Supplemental: GLAST Data CatalogSupplemental: GLAST Data Catalog

GLAST Ground Software CHEP 2007, Victoria, Daniel Flath 1 The GLAST Data Handling Pipeline...

Documents

Transcript of GLAST Ground Software CHEP 2007, Victoria, Daniel Flath 1 The GLAST Data Handling Pipeline...