pechimuthumithil/tennis-scheduler

This program implements the following scenario

Tennis-Scheduler

Please note that some points about Assignment 2 are below in this ReadMe.

Assignment 1

This program implements the following scenario.
There are 4 Tennis courts and players arrive randomly to play.

Characteristics of the player:
Gender: M or F
Game Preference: S, D, b, B
S -> Singles (2 players),
D -> Doubles (4 players),
b -> first preference S and second preference D
B -> first preference D and second preference S
Each game lasts for 'x' minutes where x is:
Singles Game
Male: 10 min
Female: 5 min
Doubles Game
Male: 15 min
Female: 10 min

A game can consist of both M and F players. In such a case, take game time to be that of a M player.

Executing The Scheduler

Compile Scheduler.c

gcc Scheduler.c -o scheduler

Prepare the inputs

The inputs should be prepared as a csv file in the following format
Player-ID Arrival-time Gender Preference
1 1 M S
2 1 F S
3 2 M S
4 3 M b

A sample is provided for reference (`input.csv')

Execute

Rung the following command to execute.

./scheduler "<input-file>"

Demo example

./scheduler "input.csv"

The output.csv that is generated will containg the results in the following form
Game-start-time Game-end-time Court-Number List-of-player-ids
1 11 1 1 2
3 13 2 3 4

Logic of the Scheduler

1. The player requests are pushed into two differnet queues based on their first preferences.
2. Games are scheduled to satisy the player's first preference.
3. Once the the games to be scheduled on based of first prefernefces are complete, the scheduler shcedules games on the basis of the second preference.
4. The game start time is the MAX(Game-end-time, Arrival-time of the last player (to play in a court))
5. Courts are assigned to a group of players from the set of 4 courts by choosing the one with the lowest Game-end-time. Game-end-time of an un-assigned court is -1

The Scheduler is multi-threaded.

                  |------------enqueueing thread------------>|  
---main thread--->|----thread to schedule single's games---->|---main thread to perform 2nd priority scheduling-->  
                  |----thread to schedule double's games---->|  

Assignment 2

For assignment 2, the required source files are client.c, server_schedule.c.
I have tried to mimic the actual world scenario in the sports complex through these programs for scheduling tennis games. Additinally, I have tried to decouple the working of the servers and the clients as much as I can.

Features

Client

1. The client.c loops through the rows of the input csv, and makes connection with the scheduling server (mimics attendant sitting in issuing complex) when the arrival time in the row is equal to the global time.
2. After this the client non-blockingly waits for a recieve from the server for 30s (one second is one minute) with respect to the global time. After which it times out.
3. If the client gets a shcedule (i.e. the set of players it will play with, start time, end time etc...) it (each client) will go to play the game by actually sleeping for the suration of the game (mimics actually entering into the court and playing).
4. After playing, every client prints out when it game was supposed to end and what the global time is at the time of printing.
5. The chidren are forked, and the game schedule contains a lot of information (court number, start time, end time, number of players, player ids), more than what is required for this assignment. This is to facilitate the building process for the upcoming assignment.
6. If a client is timed out, the the client independently opts to close it's connection without letting the server know explicitly. The server will check if a client is active before scheduling a game. I found this solution better than letting the server keep track of time.
7. Each client prints out useful information at each stage of the process.

Sceduling Server

1. This server uses OpenMP directives for multi-threading.
2. The scheduling logic is similar to the one followed by the Scheduler in Assignment 1.
3. An extra function, isClientAlive is added to allow the server to check if a client has timed out or not before incuding this client in a schedule. This is important as the server doesn't maintain any notion of time.
4. This server succesfully mimics an attendant in the sport's complex issue centre, where one asks if one can play tennis (if raquets are available and courts are free).

Running

Serever

Compile using:

gcc server_schedule.c -fopenmp -o ss

Run using:

./ss

Client

Compile using:

gcc client.c -o client

Run using:
If the input csv file is input.csv

./client "input.csv"

NOTE

The server doesn't handle the second priority of the clients. This is because we are interested into providing the player with their first preferences. So if there is player with a preference b will be waiting for a b or S preference player. Since the server doesn't know before hand if there will be a coming request that will allow the b player to play with a doubles group. Catering to the first preferences unfortunately causes us to not be able to cater to secon preferences.

Assignment 3

For this assignemnt I used MPI to covert the forked process into processes that can communicate in a world. Once the clietns are finished playing, the loosers congratulate the winners to which the winners will respond with a "Thank you" to the loosers.

Features

Client

1. Let's first understand how the ranks are assigned and what do they do. The rank 0 process is responisble for keeping track of global time. It also sends the message that a particular other rank must send to the server when the global time is the arrival time of a row in the input.csv file provided. The other processes act as clients. They behave similar to the clients described in assignment 2.
2. Other than this, the clients now greet each other in the following format src-rank src-player_id to dest-rank dest-player_id: msg.

Server

The server remains the same as before.

Running

Serever

Compile using:

gcc server_schedule.c -fopenmp -o ss

Run using:

./ss

Client

Compile using:

mpicc MPIClient.c -o mc

Run using:
If the input csv file is input.csv and it has x rows --> x player request.

mpirun -np x+1 ./mc "input.csv"

NOTE

The server doesn't handle the second priority of the clients. This is because we are interested into providing the player with their first preferences. So if there is player with a preference b will be waiting for a b or S preference player. Since the server doesn't know before hand if there will be a coming request that will allow the b player to play with a doubles group. Catering to the first preferences unfortunately causes us to not be able to cater to secon preferences.