Answer:
copy-on-write or CoW is a resources management technique used in sharing data in a computer system. It copy data by making reference to the original data when the copied one is modified. The original data is called the parent process while the copied one is called the child process. CoW allow both processes to share same pages on the memory.
The circumstance that is beneficial to use this feature is;
When the parent and child processes access the same set of program, there is implementation of the fork system call in which it shares the virtual memory. The fork system call allow the child process to run concurrently without conflict with the parent process.
The hardware support that is required to implement this feature is pagging
