Maximilian BergerDavid Gstir

Thomas Fahringer

Distributed and parallel Systems GroupUniversity of Innsbruck

Austria

Oct, 13, 2009. Krakow, PL.

OutlineMotivationArchitectureExample Use CaseConclusions

MotivationThe Grid is heterogeneousClusters are (mostly) homogeneousMultiple Architectures, Distributions,

Versions, Libraries32 / 64 BitIntel / SparcLinux / SolarisSL Linux, Redhat, Debian, etc.

Will my software run on this Grid site?

Possible SolutionsHomogenization

Make all sites equal Same Hardware Same Software

Partially done in EGEE (Scientific Linux, fixed version)

VirtualizationProvide a virtual machine which provides a

known environmentLarge Overhead!

Possible Solutions (cont.)Resource Descriptions

Every Resource published information about itselfGrid middleware uses this information to select

sitesExample: GLUE schemaProblem:

Often Incomplete! Mostly done manually

Automated Software detectionAutomatic detect installed softwareProvide this information back to the user

Softcrawl Architecture

CrawlerContains a list of plug-insEach plug-in describes

Key-Value pairs about softwareTest scriptParser component

Results are stored in database (e.g. BDII)Tests are run periodicallyIn the context of a normal userMultiple tests can be combined into one Grid

job

Example Use CaseJava Runtime Environment

Application is written in JavaIs Java installed?If so, which Version?Does JAVA_HOME point to a valid location?

Prototype implementationUses internal DBRuns in context of a personal user

Example Use Case: Script#!/bin/shecho "-- WHICH OUTPUT BEGIN --"which javaecho "-- WHICH OUTPUT END --"echo "-- VERSION OUTPUT BEGIN --"`which java` -versionecho "-- VERSION OUTPUT END --"echo "-- JAVA_HOME OUTPUT BEGIN --"echo $JAVA_HOMEecho "-- JAVA_HOME OUTPUT END --"echo "-- JAVA_HOME_VALID OUTPUT BEGIN --"[ -x $JAVA_HOME/bin/java ] && echo true || echo false

echo "-- JAVA_HOME_VALID OUTPUT END --"

Example Use Case: ValuesKey Example Value Type

Environment.java_home.exists

True Boolean

Java.binary.path /usr/lib/jvm/java/bin/java String

Environment.java_home.valid

True Boolean

Environment.java_home.value

/usr/lib/jvm/java String

Java.version.number 16013.0 Double

Java.version.string java version "1.6.0 13" Java (TM) SE Runtime Environment (build 1.6.0 13-b03) Java HotSpot(TM) Server VM (build 11.3-b02, mixed mode)

String

Example Use Case: Results

ConclusionsHomogenization is not an optionSoftware description helps Software description must be automatedUsers must be able to create testsPrototype implementation successfulCollected data can be used to create better

resource descriptionsJobs are now only run on sites where they

actually work!