Questions

The Jazz Singer in 1927

It is a useful, memory-saving technique for multiprogrammed timesharing systems. A Reentrant Procedure is one in which multiple users can share a single copy of a program during the same period. Reentrancy has 2 key aspects: The program code cannot modify itself, and the local data for each user process must be stored separately. Thus, the permanent part is the code, and the temporary part is the pointer back to the calling program and local variables used by that program. Each execution instance is called activation. It executes the code in the permanent part, but has its own copy of local variables/parameters. The temporary part associated with each activation is the activation record. Generally, the activation record is kept on the stack.

Note: A reentrant procedure can be interrupted and called by an interrupting program, and still execute correctly on returning to the procedure.

Throughput : number of processes that complete their execution per time unit.

Turnaround time : amount of time to execute a particular process.

Waiting time : amount of time a process has been waiting in the ready queue.

Response time : amount of time it takes from when a request was submitted until the firstresponse is produced, not output (for time-sharing environment).

The charophytes are the extant group of green algae that are most closely related to modern land plants.