The CIO for your company needs to decide which of two proposals for server solutions to accept to provide for the company's credit card transactions, now and in the future.  As you know, the company is a clearinghouse for credit card transactions and needs to process/validate many transactions each second and the number is expected to grow.  Consequently, it is important for the CIO to find a robust server solution.

Two sets of simulated data have been provided to test each server solution; both sets are in files.  One  file, current.dat, contains about ten minutes of transactions; in it, transactions arrive about every 6 milliseconds.  The other file, future.dat, also contains about ten minutes of transactions but with transactions arriving about every 3 milliseconds.  Both data sets have their first transaction time stamped just after 14:20 (2:20 pm) on 12 November 2006.  Both data files are in binary, Big-Endian form with each transaction consisting of

Credit card number        a long value (64-bit integer)
Purchase amount           a float value
Date                      8 bytes of ASCII codes in the form   mm/dd/yy
Hour                      a byte (hour of the transaction)
Minute                    a byte (minute of the transaction)
Millisecond               an int (No. of milliseconds into the minute)

All transactions have a unique time stamp indicating their arrival at the clearinghouse for service.  You can find both data sets on the I: drive in   I:\jlwolfe\310\s07

You are to write two programs that simulate the way the two proposed server solutions will handle these transactions.  Each program needs a simulator to control the action.  The simulator contains a clock that starts at 14:20 and increments each millisecond.

• If at a given millisecond a transaction arrives, the simulator must put it on a server queue.

 
• If at a given millisecond a server is available and there is a transaction waiting, the simulator must remove the transaction from the server's queue and give it to the server.

 
• If at a given millisecond, a server is finished with a transaction, the simulator must gather statistics about the transaction and make the server available.

 
• It is entirely possible for all or any combination of these actions to take place in the same millisecond.  The simulator should check for each action once per millisecond in the order listed.

In one server solution, there is a single server which takes exactly 2 ms to process a transaction.  That is, once a transaction is given to the server, the server will finish the operation in exactly 2 ms.  In the other solution, there are 10 servers, each of which takes exactly 7 ms to process a transaction.  To do load leveling with the 10-server solution, the last digit of the credit card number will be used to choose which server will handle a particular transaction.  Naturally, the single server solution has a single queue for waiting and the 10-server solution has ten queues, one for each server.

The CIO requires you to produce two critical statistics about each server solution.

1. The average service time for a transaction.  The service time for a transaction is the sum of the waiting time (how long it is in the queue) and the server processing time.  Average service time of 10 ms or less now and in the future is required to be acceptable.

 
2. The maximum queue length.  This is the maximum number of transactions waiting for a server.  The CIO requirement is that the maximum queue length times the server processing time (i.e., 2 ms or 7 ms) must be less than 50 ms.

You will need to execute each program twice to provide the required information, once with the current.dat file and once with the future.dat file. So, it is probably best to prompt for the file name.   All output should go to the console.  You should expect these executions to take a little time; both data sets contain very many transactions.

Hand in a printout of your well documented programs.  For those classes that are common to both programs, just print them once and note at the top that they are common to the two programs.  Also hand in a printout of the captured console output  for the program executions.  Make a p5 folder under the folder named after you on the P: drive and put in it the .java files for the two programs. Do NOT put the data files in this folder.

Extra Credit:  Determine the fewest servers with 7 ms service time which can satisfy the CIO's criteria of an acceptable solution for the future data.  Show a simulation report that supports your conclusion.
 

To give you an idea of what sort of report to generate for the CIO.  Here is what my program generated for current.dat on the single-server solution.

Simulation ends after 599152 milliseconds
100012 transactions handled
Maximum queue length: 5
Average service time:  2.417 milliseconds