One Minute Evaluations for 21-23 September 2004

CS 438-505 - Operating Systems Concepts

• Topic: We learned about process/process management.

  Question: Should OO techniques be introduced into OS development?

  One minute response: OO techniques tend to involve expensive run-time behavior, such as virtual-function resolution and heap storage management. To the extent that these costs can be reduced, then OO techniques can be used in OS development.

• Topic: We spoke about process management.

  Question: Still not clear about the simulator and how that works on OS?

  One minute response: The simulator is like hardware, it simulates hardware; the OS works on the simulator (that is, the hardware).

• Question: Is there any other books other than Nutt?

  One minute response: Yes, but I don't think they're as good. I just gave a few OS books to the library; you might want to check them out.

• Topic: Process management concepts, def. process, virtual machine, def. thread, threads.

  Question: Nothing yet, but soon I will have plenty of ?'s.

• Topic: This week we talked about processes, threads, and finite-state machines.

• Topic: I learned the difference between a process and a thread.

  Question: In your opinion would it be a good idea to make a process class with a thread child class for this program? Explain.

  One minute response: No. You should do the simplest thing possible, and that doesn't involve implementing threads.

• Topic: We learned about threads.

  Question: How does the CPU know what thread to work on?

  One minute response: The scheduler tells it.

• Topic: We talked about processes, about process management, about how threads and processes are different.

• Question: How does dynamic sharing get allocated? What is the process state?

  One minute response: It depends on how sharing is done, but the usual methods, such as via files, is allocated as normal. A processes state is a description of the process's current situation, such as running, waiting, and so on.

• Question: Can a puma challenge a lion for the role of King of the Jungle? Also with process hierarchy, couldn't a parent just introduce the new child to its siblings and keep pointers to their siblings.

  One minute response: Yes, that's effectively what has to be done.

• Topic: We talked about process management and the indirect and direct ways in managing processes and threads.

  Question: You talked about interprocess communications. Is it possible to talk to two different processes without going down to the OS?

  One minute response: Without the OS all you've got is hardware, so the OS has to be involved at some level. But yes, it is possible; that's what's know as covert communication.

• Topic: Process management: You said processes can be thought of like structures.

  Question: How can we represent resources like printers? Why should threads be handled by OS? Why not within the process?

  One minute response: Processes don't own printers the same way they own open files, for example. The process that does own the printer probably does so via a file descriptor to the port associated with the printer.The process has no access to the CPU and the OS does, so it makes more sense for the OS to handle threads. However, user-space threads are managed by the process (in some sense).

• Topic: We talked about processes and threads and managers for each.

  Question: No questions as of now.

This page last modified on 16 July 2003.