Questions about how operating systems decide which process to execute at which time.
Questions tagged [process-scheduling]
154 questions
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How does CFS prevent a long sleeping task from occupying the CPU?
The Completely Fair Scheduler executes the task that has so far received the least share of CPU time and is thus the most 'disadvantaged'.
So if a task sleeps for a really long time, say 3hrs, how does CFS prevent this task from being executed for…
portux
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Scheduling identical jobs with Cmax/Ci
I have $x$ uniform machines that are identical, except that each runs at a different speed; machine $j$ runs at speed $s_j$. I have $n$ identical jobs. Each machine can handle one job at a time. The time to complete a job on machine $j$ will be…
Simon
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1
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Number Partitioning targeting a Ratio of subset sums?
I have a problem, which appears to be similar to number partitioning:
a set of numbers partitioned (two-way), such that the sum of the numbers in each subset are as close as possible to a targeted ratio (instead of having the minimum difference, as…
kavadias
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1 answer
Processor Scheduling (SJF / FCFS)
So I know that scheduling has been covered in other articles, but because my provided values are different and decimals are used, I am having difficulty wrapping my head around it. I have reviewed all of the other posts already but would like…
asyncle
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Round Robin time slice(quantum time)
In all books about this topic, I read that there is a rule of thumb is that 80% of the process execution time is lower than time slice. But how do I calculate this value? I looked at every article possible and I found like nothing. Can someone help…
Cipri
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Where to start on SJF Cpu schedualing homework problem?
So the question is;
For the following three jobs:
P1: 10 (3,2,5); P2: 4 (2,2); P3: 16 (2,3,5,6)
Execute the three jobs using Exp Ave Alpha =0.6, default=2
I know the formula to get the exponential average for a process is
Pn+1 = (alpha) * Tn +…
CryptoJones
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Does a time quantum affect priority non preemptive scheduling?
I am given a list of processes with their arrival time, CPU, time and Priority. The time quantum is given as 2 seconds. A lower priority number translates to a higher priority.
(process #, arrival time, CPU time, Priority)
-P0: 0, 8, 5
-P1: 2, 2,…
bkennedy
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Why round robin favours the process with large burst time?
From the round-robin wikipedia
In the absence of time-sharing, or if the quanta were large relative to the sizes of the jobs, a process that produced large jobs would be favored over other processes.
Isn't that obvious? I mean if burst time of…
tbhaxor
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Context Switching in Round Robin CPU scheduling algorithm
If we have only one submitted process and we are using RR CPU scheduling algorithm. Assume that the CPU burst time for this process is 10 ms and the time quantum is 2 , then there will be multiple context switches ? OR the process will continue…
AAA
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Round Robin, confused about how to processes are handled related to arrival order
See this picture, in parentheses are (arrival time, execution time required)
Why doesn't the "p5" process is processed before "p6"? Why do p3 and p4 are finished and p5 is executed only after the processes that arrive at "11" are executed?
Diego Alves
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Arrival Time vs Burst Time vs Priority Time? If Priority Time is the same, which process dispatch first?
The question is based on if we have the same Priority value when we are given:
Arrival Time = AT, Priority and Burst Time=BT.
1.Say if we a table with AT, Priority and BT. To dispatch a process it is obvious that we check the AT first since we…
JustinC
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