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I ran screaming from Symbian OS and pledged to never buy another Nokia product about 6 years ago because of this specific topic. I worked with Nokia on a few development projects.
Symbian's scheduler (back then) was a strict priority queue. Instead if proper threads and processes, it was simulated through an "Active Object Queue" which was very simplistic and barely functional. The idea was, you had a list of cooperative threads (windows 3.1 style) and the first item in the list flagged as needing attention was the next item run. So, if you were to release control from a high priority object and want it back after, it would get control immediately and starve all other threads.
Later, they added a "kernel scheduler" which was "real-time" but was little more than an interrupt handler with a limited scheduler. The overall goal of the OS design was "it doesn't matter how back the OS sucks, we can run on a lower end CPU than windows CE." So while Windows CE was a full, preemptive multitasking real-time kernel. Symbian was basically something closer to a kernel with a real-time process and a non-real-time process.
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How a Round Robin scheduling algorithm allocates the CPU to processes?
The round-robin scheduling algorithm allocates CPU time to processes by sequentially assigning the CPU to processes of equal priority that are in the state of being able to use the CPU. (Not blocked) This works by appearing to evenly distribute the CPU amongst CPU ready processes. Processes that are waiting on something, such as an I/O event, particularly waiting on the user to press Enter, are not considered for allocation. Often, there is a priority assigned to the process, which factors in the allocation strategy. Processes that are mostly I/O intensive tend to have higher priority, giving them good response time. Processes that are mostly CPU intensive tend to have lower priority, so they don't interfere with overall system responsiveness.
List down the names of any three parameters on which you analyze an algorithm?
what is algorithm and its use there and analyze an algorithm
Which CPU scheduling Algorithm is used by Windows XP OS?
In the past (and perhaps currently as well) it has used round-robin, at one time 1 second but since updated to .1 seconds. It may also have other features such as preemptive abilities. Priority fair scheduling.
What is the use of an algorithm to scramble data into a format that can be read only by reversing the algorithm?
Encryption
How do you use lempel ziv algorithm?
how to use lempel_ziv encoding ?
What CPU scheduling algorithm is used by?
same as linux use.
How a Round Robin scheduling algorithm allocates the CPU to processes?
The round-robin scheduling algorithm allocates CPU time to processes by sequentially assigning the CPU to processes of equal priority that are in the state of being able to use the CPU. (Not blocked) This works by appearing to evenly distribute the CPU amongst CPU ready processes. Processes that are waiting on something, such as an I/O event, particularly waiting on the user to press Enter, are not considered for allocation. Often, there is a priority assigned to the process, which factors in the allocation strategy. Processes that are mostly I/O intensive tend to have higher priority, giving them good response time. Processes that are mostly CPU intensive tend to have lower priority, so they don't interfere with overall system responsiveness.
Which type of process scheduling does Linux and window uses?
Linux has a number of schedulers available in its kernel, plus at least one scheduler available as a patch. But the default schedler is the Completely Fair Scheduler. Like most modern schedulers, it is pre-emptive, meaning that instead of the process deciding when to give up the CPU, the kernel decides for it when to give up the CPU. This keeps even the most uncooperative process from starving the other processes on the computer of CPU time. From what I understand of how CFS works: It keeps an eye on how much of an assigned quantum (length of time.) is actually spent on the CPU by a process and how much of the quantum is spent blocking (Keeping off the CPU to wait for I/O requests to complete, a process can't usually proceed and keep going without requested data. During the time a process is waiting for the hardware, other processes make use of the CPU.) The less time a process actually uses the CPU on its given quantum, the higher a priority it gets so that when the data from an I/O operation is complete the process can quickly execute to the next I/O request and block again. This keeps the CPU busy, but the system responsive to just about any event.I don't know what sort of process scheduling is used on Windows. Windows, unlike Linux, is given a pretty heavy black box treatment when it comes to its users and a great deal about its kernel is not common knowledge. Presumably it is a pre-emptive, priority-based scheduler. Doubtful it's as efficient as CFS.
How do you play android game in symbian phone?
Android and symbian is different System, so if you want to play android game on it, you must use android emulator on your symbian.
What is online scheduling and offline scheduling?
Online scheduling is the useage of competitive analysis (or online algorithms) on scheduling problems. Online algorithms is characterized by making decision "online", which means a point in the time axe. In this point of time, we can not see the future jobs or tasks, whereas we only know the jobs or tasks before or at this point of time. In contrast, in offline scheduling problems, there is no the conception of "point of time". We are lords of the world. We stay outside the real world and can see the past and future (jobs or tasks). TThis aspect is called "offline". Since we can see the past and the future, we know the total knowledge of the problem before we make decision (not depending the time). Even use the simpliest method, such as enumeration, then we can obtain the optimal solution. Nontheless, by not knowing the future knowledge of problem, we must make decision. Then we use a critierion to meaure the performance of online algorithm, called competitive ratio. This is a conception like approximation ratio, compering the objective value obtained by online algorithm and that of offline (optimal) algorithm. Offline scheduling is concerned of the classical scheduling problems. Not introducing the conception of "online". Offline scheduling problem is scheduling problem.
Which phones use the Symbian OS?
samsung
Is Nokia c7 anaroid?
If you mean Android OS, then no. Nokia C7 use Symbian Anna (previously Symbian^3 and Symbian Belle some time later) as it's OS.
What is the definition of CPU?
A CPU scheduler maximizes CPU utilization. It can do the scheduling based on two types, which is either a preemptive or a non-preemptive scheduling.
What is disk scheduling in operating system?
why we use disk scheduling in c ?
Which symbion use in nokia e63?
symbian S60-based smartphone
What strategy can a computer user employ to maximize the amount of CPU time allocated to the user's process at multi level queue scheduling?
The program could maximize the CPU time allocated to it by not fully utilizing its time quantums. It could use a large fraction of its assigned quantum, but relinquish the CPU before the end of the quantum, thereby increasing the priority associated with the process.
What is role of reservation station in Tomasulo's Algorithm?
Reservation Stations are decentralized features of the microarchitecture of a CPU that allow for register renaming, and are used by the Tomasulo algorithm for dynamic instruction scheduling.Reservation stations permit the CPU to fetch and re-use a data value as soon as it has been computed, rather than waiting for it to be stored in a register and re-read. When instructions are issued, they can designate the reservation station from which they want their input to read.
