CSCI 365 Introduction to Large Scale Computing

CSCI 365 Introduction to Large Scale ComputingIntroductionsNameYearMajorWhy you are taking this course? Acceptable answers:I am interested in the subject...I needed to fill an upper-level elective...My advisor told me to take the course...What is Large Scale Computing?Large Scale ComputingDeveloping really big applicationsFocused on highly available, transaction processing systemsApplications support or solve complex problemsTechnologies:Mainframes (IBM System Z, HP NonStop)Distributed / cloud

Capabilities of a Large Scale SystemLarge scale transaction processingThousands of transactions per secondSupport thousands of users and programsSimultaneously access and manage shared resourcesDatabase storage in TerabytesLarge bandwidth communications

About MeWidener Computer Science graduateHelped setup the initial large scale course at Widener in participation with the IBM academic initiative6+ years experience in large scale application development at JPMorgan ChaseCurrently in the Mortgage Banking line of business

Credit Card Processing SystemWhat does a credit card processing system do?Authorizations: what happens when you swipeStatements: transaction history, rewardsCustomer & account system of recordInteract with network (Visa, MasterCard, acquirers)Stats:150MM accounts20MM transactions per day (peak 600TPS)Response time under 200msCourse OverviewCourse ObjectivesUnderstand key concepts required for large scale application development regardless of technologyDescribe programs from an application architecture perspectiveGain real world insight into the use of computer science conceptsCourse Objectives contUnderstand the difference in creating applications which run on a PC, web-based applications, and large scale applicationsBecome fluent in TLAs / buzzwords

Course TopicsSystem architecture overviewIntroduction to COBOL and JCLData organization and access methodsApplication architecture (SDLC)Databases: relational vs. hierarchicalTransaction processingHigh availabilitySecurityCourse FormatLecturesReview key conceptsApplied and conceptual topicsLabsHands on mainframe experience (see next slide)Application development assignmentsOnlineUtilize and contribute to our course wikilargescalecomputing.wikispaces.comHands on Lab ExperienceLab exercises will be completed on an IBM z9 mainframe at Marist CollegeMade available through the IBM academic initiativeWe use a terminal emulator to connect to the system from either the classroom or your personal computerCourse WikiWiki contentsCourse info (lecture slides, labs, schedule, etc)General large scale computing informationStudents are expected to utilize the wiki and become active contributorsCourse Grading5% lab 120% lab 220% lab 320% exams (2)5% lab presentation20% final exam10% participationData sets & TSOLecture 1Quick BackgroundIBM mainframe operating system is referred to as Z/OS

What is a Data Set?Z/OS files are called data setsA data set is a collection of logically related data records stored on diskBefore data can be written to a data set, it must be allocatedA data set can contain:Source programMacrosData records used by a programTypes of Data SetsThere are two basic types of data sets:Sequential data setData stored in a single piece of allocated disk spacePartitioned data set (PDS)Data can be sub-divided into multiple individual chunks or files (members)12345678901234567890123456789012345678901234567890....

SequentialPartitioned123456MembersData Set Naming ConventionsSample data set name:KC02124.LAB1.COBOL

High Level Qualifier: username or catalogUser Determined Qualifier: what this data relates toType: what type of data is contained (similar to a file extension)High Level QualifierTypeUser Determined QualifierData Set Naming Conventions contMaximum of 22 name segments (qualifiers)Level qualifiers separated by .Each level qualifier:1 to 8 charactersFirst character must be alphabetical (A-Z) or special (@#$)Remaining: alphabetical, numeric (0-9), or hyphenUpper case only (not case sensitive)Example: KC02124.CSCI365.LAB1.COBOLPDS Naming ConventionsSame rules as sequential data setsNeed to specify a member name within the data set:

KC02124.LAB1.COBOL(HELLO)

KC02124.LAB1.COBOL(FUBAR)123456Sequential vs. PartitionedTypically, we will use the different data set types as follows:Sequential: raw data filesPDS: COBOL source / executables, JCL, etcPhysical Data Storage on Z/OSData is stored on a Direct Access Storage Device (DASD)DiskMagnetic tapeOptical mediaWhen you hear DASD you should think diskUsed for storing the OS, data sets, databases, etcEBCDICIBM systems since the S/360 use the Extended Binary Coded Decimal Interchange character setDeveloped before ASCII and is also an 8 bit character setZ/OS also supports ASCII and UNICODE for web / Java useCatalogsA catalog associates a data set with the volume on which it is locatedLocating a data set on a catalog requires:Data set nameVolume nameUnit (volume device type)Z/OS UNIX File SystemZ/OS UNIX System Services (USS) allows Z/OS to access UNIX filesFollows UNIX standard directory / file structureWe will not be using USS in this courseHow do we Interact with Z/OS?TSOAllows users to log on to Z/OS and use a limited set of basic commands This is called using TSO in native modeThink command line interfaceISPFMenu structure which sits on top of TSO and provides a simpler interface for accessing commonly used TSO functionsTSO OverviewTSO stands for Time Sharing OptionAllows users to create an interactive session with Z/OSBasic command promptLab Pre-TasksCreate a login and request to be a member of our wiki:largescalecomputing.wikispaces.comReceive your TSO useridDo not forget your ID!Lab 1Lab 1 is taken from IBMs Master the Mainframe contestFollow the instructions on the wiki:http://largescalecomputing.wikispaces.com/Lab1Hints:Return does not equal CNTLDo not forget your password!