Projects

Multi-core Process Queue Simulator

This project simulates a multi-core process queue that receive a series of jobs and schedule them to run on multiple CPU cores as separate processes using one of the selected scheduling policy (FIFO, Round Robin, MLFQ). The process queue as two components, a server and a client.

The server maintains a queue of running jobs, waiting jobs and schedule them according to the scheduling policies.

The client allows the user to send jobs for the server to schedule and query the status of running and waiting jobs. It supports sending the following commands to the server:

• ADD command : sends the "command" to the server to schedule
• STATUS : gets the summary of running and waiting jobs, average turnaround time and response time
• RUNNING : gets the list of all running jobs
• WAITING : gets the list of all waiting jobs
• FLUSH : removes all jobs and terminates all active or suspended processes

$ ./pq -h

Usage: ./pq [options]

General Options:

-h                 Print this help message
-f PATH            Path to IPC channel

Client Options:

add COMMAND        Add COMMAND to queue
status             Query status of queue
running            Query running jobs
waiting            Query waiting jobs
flush              Remove all jobs from queue

Server Options:

-n NCPUS           Number of CPUs
-p POLICY          Scheduling policy (fifo, rdrn, mlfq)
-t MICROSECONDS    Time between scheduling

Click here for Multi-core Process Queue Simulator repository

Rorschach Directory Scanner

This is a program that monitors a directory and examines all files under the directory to determine if any files have been created, modified or deleted. If any of those events occur, an action on the file would be executed if the name of the file matches any of the patterns specified in a rule file.

The rule file is a simple text file with lines in the format of:

EVENT PATTERN ACTION

To run the program, compile the source code with "make" and run the executable with the following arguments:

$ ./rorschach -h

Usage: rorschach [options] ROOT

Options:

-h          Print this help message
-f RULES    Load rules from this file (default is rules)
-t SECONDS  Time between scans (default is 5 seconds)

Click here for Rorschach repository

Texas Hold'em Simulation with AI

This is a fully implemented command-line based Texas Hold'em Poker Game with odd calculation. ASCII graphics and AI players using C++. It follows the fixed limited betting and ante rules. It utilizes the STL::<unordered_map> to store rankings of different hands and uses the Monte Carlo approach to simulate the probability of winning based on player's hand and the community cards.

Click here for Texas Hold'em repository

Web Server

In my system programming course, one of the final projects was to create a web server which can handle file requests, CGI script requests and directory browsing requests. It was implemented using C system calls and can handle request one by one or by forking. A python script and several shell scripts were also created to benchmark the latencies and throughputs for forking and single. To see results of the benchmark and analysis, please click the link below to the blog post or read the README.md in the Github repository.

p.s. The thumbnail picture is a meme of one of my group members

How forking affects latency and throughput of server

Click here for Web Server repository

Partial re-implementation of find

This is an partial re-implementation of the linux find command using C system calls that deal with files, directories, and processes. Similar to find, search recursively searches a directory and prints items it finds based on the specific options:

$ ./search -help

Usage: ./search PATH [OPTIONS] [EXPRESSION]

Options:

-executable     File is executable or directory is searchable to user
-readable       File readable to user
-writable       File is writable to user

-type [f|d]     File is of type f for regular file or d for
                directory

-empty          File or directory is empty

-name  pattern  Base of file name matches shell pattern
-path  pattern  Path of file matches shell pattern

-perm  mode     File's permission bits areexactly mode (octal)
-newer file     File was modified morerecently than file

-uid   n        File's numeric user ID is n
-gid   n        File's numeric group ID is n

Expressions:

-print          Display file path (default)
-exec cmd {} ;  Execute command on path

Click here for Search repository