Transcript Poor performance in implementation

Poor Performance in
Implementation
CS524 – Software Engineering
Azusa Pacific University
Dr. Sheldon X. Liang
Mike Rickman
Performance Problems
• Performance
• Time required to perform necessary tasks
• How can there be performance problems
• Fast, inexpensive hardware
• Optimized software
• Fast Networks
Performance Problems
• The system simply cannot operate fast enough
• The slowest things computers do:
• Talk to external storage
• Talk to people
• “Huge” problem
• Database transactions
• Number of users
Reliability Problems
• Are reliability and performance problems
related?
• Reboots
• Cancelation
• Jitter Finger
• For Hopper Specialty Company it’s difficult to
decide which was worse
• Performance
• Reliability
Hopper Specialty Company
• Distributor of Industrial Hardware
• Supplier to Oil & Gas drilling companies
• Thousands Inventory Items
• Estimated $3.5 million annual sales
• Purchased NCR’s Warehouse Manager system
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$180K purchase price
Tracks “huge” inventory
Pricing
Automatic order points
Instant Invoicing
Had over 200 successful installations
NCR’s Warehouse Manager
• What it really was
• NCR suspended sales of Warehouse Manager
• Working out “critical bugs”
• Inadequate testing
• Warehouse Manager ported to NCR operating
system
• Original software from Taylor Management
• Designed for Burroughs Operating System
• 200 Successful installations on Burroughs OS
Forty failed installations on NCR OS
NCR’s Warehouse Manager
• Deadly Embrace
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System slows to a crawl
Long lines of customers waiting
Operations expected in seconds takes minutes
Two terminals accessing same data
• Silent Death
• Solution to Deadly Embrace
• LogOff - LogOn
• Corrupted data resulted
• Twenty to thirty restarts per day
Hopper’s Demise
• Incorrect Pricing
• $17 / ft. item became $30 / ft.
• Incorrect Inventory
• Show 50 items on hand when 50 items needed to
ordered
• Lost Business
• $350K annual contract cancelled
Hopper’s Demise
• Insult to Injury
• NCR claimed other customer did not have problems
• Several similar complaints documented at NCR
• Blamed Hopper’s employees for failures
• Not properly trained
• Stocking Static Defense
• NCR employee blamed problems on static electricity from
a workers nylon stockings
Result
• NCR purchased by AT&T Global Information
Systems
• Warehouse Manager Abandoned
• AT&T admits problems
• Hopper sues
• Past statue of limitation
• Restrictive Sales Agreement
• Arbitration
• Computer Ethics 101
Implementation
Personal Experience
• The difference between software engineer and
software architect
• Automated Test
Equipment
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Computer
LED Driver
Optical Spectrometer
Data Acquisition
Data Storage
Configuration
Processing Algorithms
Personal Computer
usb
Mini Model
Spectromete
Fiber Optic
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Sensor Fixture
Serial
Implementation
Personal Experience
• Software Engineer View
• Test Operator
• One Button Test
System
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Characterize Sensor
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Actor1
Line Operator
Implementation
Personal Experience
• Software Architect View
• Installation
I
• Operation
O
• Maintenance
M
Implementation
Personal Experience
• Software Architect View
• Installation
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Software Installation
Power Requirements
Environmental Conditions
Calibration
• Operation
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Identify Sensor from job traveller
Specify lot number
Place sensor in fixture
Start Process
Determine Pass/Fail
• Maintenance
• Calibration
Questions?
Reference
Glass, Robert Software Runaways
Upper Saddle River, NJ 1998