Questions about how operating systems decide which process to execute at which time.
0
votes
2answers
67 views
Disk scheduling and process scheduling
Whats the diffrence between Disk scheduling and process scheduling? I mean i know the roles of disks and processes, but it seems to me they both have the same aim. to reduce monopolies, they even both ...
0
votes
0answers
59 views
The convoy effect in process scheduling
As I understand the convoy effect, in the context of vehicular traffic in a road system. A slow moving group of vehicles passes through the system, slowing traffic even in areas which were not ...
3
votes
1answer
119 views
What is the difference between Multiprogramming and Multitasking
I am finding it difficult to clearly differentiate between Multiprogramming and Multitasking.
My primary source has been Wikipedia, but the WP article seems to be a little at odds with some less ...
1
vote
2answers
61 views
What mechanisms prevent a process from taking over the processor forever?
Suppose a process keeps running code (e.g. an infinite loop). How can other programs take over? What prevents the process from remaining active forever?
1
vote
1answer
65 views
Process state in multi threaded process
What would be the process state in a multi threaded process, in which threads are in different states (running, waiting, blocked etc)
1
vote
1answer
191 views
Scheduling algorithms and quantum time
I would like to know what impacts does a scheduling algorithm say Round Robin of FIFO have on a Operating system. I understand the a scheduling algorithm has the processes run in burst then switch ...
3
votes
1answer
472 views
First-Come-First-Serve scheduling algorithm - what happens to process after returning from I/O? where does it go in the queue
There are three processes in line
P0, P1, P2
1) P0 registered and executes
2) P0 I/O blocked
3) so P1 executes
4) P1 I/O blocked
5) P0 executes. ??
After P1 must come P2 that is what FCFS ...
4
votes
1answer
240 views
How are threads implemented in different OSs?
I was reading Linux Kernel Development by Robert Love, where I came across this
Linux takes an interesting approach to thread support: It does not
differentiate between threads and normal ...
6
votes
4answers
709 views
What is meant by interrupts in the context of operating systems?
I've decided to read Operating Systems Concepts by Silberschatz, Galvin Gagne (8th edition) over the summer. I've gotten to a topic that's confusing me - interrupts and their role as it relates to ...
4
votes
1answer
3k views
What is the average turnaround time?
For the following jobs:
The average wait time would be using a FCFS algorithm:
(6-6)+(7-2)+(11-5)+(17-5)+(14-1) -> 0+5+6+10+13 -> 34/5 = 7 (6.8)
What would the average turnaround time be?
4
votes
1answer
675 views
Which queue does the long-term scheduler maintain?
There are different queues of processes (in an operating system):
Job Queue: Each new process goes into the job queue. Processes in the job queue reside on mass storage and await the allocation of ...
7
votes
2answers
383 views
Round-robin scheduling: allow listing a process multiple times?
In a round-robin scheduler, adding a process multiple times to the process list is a cheap way to give it higher priority.
I wonder how practical an approach this might be. What benefit does it have ...
11
votes
4answers
375 views
Does cooperative scheduling suspend processes when they perform an I/O operation?
Many operating systems references say that with cooperative (as opposed to preemptive) multitasking, a process keeps the CPU until it explicitly voluntarily suspends itself. If a running process ...
