Team Members:

• Daniel Abramovich   dabramov@cs.cmu.edu
• Justin Kenlon   jkenlon@andrew.cmu.edu 
• April Navarro   apriln@cs.cmu.edu
• Kevin Steppe   ksteppe@cs.cmu.edu

Task Allocation:

• Baseline Application
• Fault-Tolerant Baseline Application
• Real-Time Fault-Tolerant Baseline Application
• High-Performance Real-Time Fault-Tolerant Baseline Application

Baseline Application Description: 

• An application that will give real-time stock information and on-demand stock trend analysis.

Configuration:

• Middleware:  J2EE, JBoss
• Operating System:  Linux
• Language:  Java
  

Third-party software, if any (databases):

• MySQL
  

Baseline Application Features:

• Clients can retrieve a list of available stocks from the server.
• Clients will be able to select from the list of available stocks which stocks they are interested in and save this information in a user profile, associated with a user name.
• Clients will be able to retrieve a saved profile back from the server.
• Stock price information will be displayed at the client for each stock selected in the loaded profile and will be updated periodically.
• Additional trending information will be displayed for a stock when requested by the client.

Reliability Requirements:

• If a server crashes, it will restart automatically.
• If a server crashes, the client will detect that the server has crashed and automatically failover to another server within 1 minute.
• A client's profile information will still be available if the client must failover to another server.
• No incoming stock information will be dropped/lost if a single server fails.

Real-Time Requirements:

• Stock update information should reach the client within 5 seconds after it is received by the server.
• An operation to save or retrieve a profile should complete within 30 seconds.
• An operation to request trending information for a stock should be completed within 40 seconds.

Performance Requirements:

• The system will be able to service 15 concurrent clients.
• Each client should be able to subscribe to up to 20 stocks at one time.
• The system will be able to handle 5 concurrent requests for trending information.

Baseline Application

Interfaces

    Javadoc Pages  - this is the initial draft of the interfaces (see the architecture diagram below for the updated interfaces)

Scenarios/Interactions

• The first scenario implemented was the simple use case where the user enters a name and list of stocks.  This is then stored in the database and can be retrieved.

Current Status

    The following requirements have been implemented:

• Clients can retrieve a list of available stocks from the server.

• Clients will be able to select from the list of available stocks which stocks they are interested in and save this information in a user profile, associated with a user name.
• Clients will be able to retrieve a saved profile back from the server.
• Stock price information will be displayed at the client for each stock selected in the loaded profile and will be updated periodically.

    The following requirement has been placed on hold (this was discussed with Priya on 2/9 as a way to reduce the scope of the Baseline application):

• Additional trending information will be displayed for a stock when requested by the client.

Documentation

• Architecture    (vsd)
• Javadoc Pages
• INSTALL.txt

Test Scripts

• README.txt

Downloads

Fault-Tolerant Baseline Application

Scenarios/ Interactions

• Scenarios

Current Status

    The following requirements have been implemented:

• If a server crashes, it will restart automatically.
• If a server crashes, the client will detect that the server has crashed and automatically failover to another server within 1 minute.
• A client's profile information will still be available if the client must failover to another server.
• No incoming stock information will be dropped/lost if a single server fails.

Documentation

• Architecture - Deployment   (vsd)
• Architecture - Run Time       (vsd)
• Javadoc Pages
• Setup, Installation & Run Instructions

Test Scripts

• Test 1 - Start All Servers from Replication Manager
• Test 2 - Replication Manager restarts a server
• Test 3 - Transfer stock cache from an existing server to a newly started server
• Test 4 - Client failover
• Test 5 - Stock Ticker server connection (reconnect to server)

Fault-Injection

• The fault injection is taking place from the Replication Manager.

• The injection works by allowing a user to inject faults in the following ways:

  -  select an individual server to kill by selecting a hostname

  -  select kill all servers

  -  select kill Replication Manager

• Faults are injected by:

  -  set user to ksteppe

  -  ssh to the designated machine

  -  poll for process that are associated with our server processes

  -  kill -9 all identified processes

• There is a static CrashFaultInjector class that is called by the Replication Manager

Downloads

Real-Time Fault-Tolerant Baseline Application

Timing Measurements

• Round-Trip Time
• Server Side Measurements

Scenarios/Interactions

• Scenario and interaction specifications have not changed.  (see FT-Baseline-Scenarios )

Current Status

• Application has been tested and average/worst-case timings analyzed
• Performance bottlenecks have been identified:

            JBoss startup times, server reference lookup, database transactions

• Plans have been made to cure these issues, which will smooth out the timings and give us a degree of higher performance.

High-Performance Real-Time Fault-Tolerant Baseline Application

Timing Measurements (Active vs Caching vs Baseline)

• Fault-Free timings
• Fail-over timings
• Normal Operation w/ Fault-Injection timings

Documentation

• Architecture - Deployment
• Architecture - Run Time       (vsd)
• Setup, Installation & Run Instructions

Current Status

• Baseline, background server caching, and active replication clients have been implemented
• JBoss startup timing normalized
• Replication Manager timing issues (server initialization, etc) fixed
• For active replication, if at least one server is alive, fail-over times are cut in half.

Scenarios/Interactions

• Scenario and interaction specifications have not changed.  (see FT-Baseline-Scenarios)

Downloads