Archive: Concurrent Computing OS Coursework

Note: Unfortunately the original notes document submitted with this coursework was lost when SAFE was decommissioned in October. The below list is not a full technical specification but does a good job of outlining the functionality of the OS.

This OS provides:

• A weighted round-robin scheduler based on timer interrupts
• An alternative priority-aging scheduler
• fork(), exec(), kill(), yield() and nice() system calls for process handling
  • New execx() system call to start a program with an argument
• Semaphores to lock system resources, supported by two new system calls
• Per-process file descriptors supporting redirection
• Pipes
• An inode-based file system supporting
  • Directories and hierarchy
  • Relative paths
  • Large file support
  • Multi-block caching
• A new built-in shell, xsh, to make use of all the above features.

Repo contents:

• device/: Hardware libaries
• kernel/: Kernel mode programs, including the kernel and file system
• user/: User mode programs such as xsh, philosophers, and cat