1. Job scheduler is also called long term scheduler and CPU scheduler is called short term scheduler.
2. Job scheduler selects the processes from the job pool and load them in to the memory for execution. in other hand CPU scheduler selects among the processes that are in ready to execute and allocate the CPU to one of them.
3. CPU scheduler is faster than the process scheduler.
Jobs or processes are the same.
Whereas, Job scheduler and CPU scheduler are two different terms.
Job scheduler is also called long term scheduler and CPU scheduler is called short term scheduler.
While Job scheduler selects the processes from the job pool (Job pool is on the Hard disk) and load them in to the memory (Main Memory or RAM) for execution. in other hand CPU scheduler selects among the processes (in RAM) that are ready for execution and allocates the CPU to one of them.
Hope I got it right and answered your query. Sorry for any mistakes as I'm not perfect as well. :)
Cheers,
KV
1. Job scheduler is also called long term scheduler and CPU scheduler is called short term scheduler.2. Job scheduler selects the processes from the job pool and load them in to the memory for execution. in other hand CPU scheduler selects among the processes that are in ready to execute and allocate the CPU to one of them.3. CPU scheduler is faster than the process scheduler.Read more: What_is_the_difference_between_the_job_scheduler_the_CPU_scheduler
Jobs or processes are the same. Whereas, Job scheduler and CPU scheduler are two different terms. Job scheduler is also called long term scheduler and CPU scheduler is called short term scheduler. While Job scheduler selects the processes from the job pool (Job pool is on the Hard disk) and load them in to the memory (Main Memory or RAM) for execution. in other hand CPU scheduler selects among the processes (in RAM) that are ready for execution and allocates the CPU to one of them. Hope I got it right and answered your query. Sorry for any mistakes as I'm not perfect as well. :) Cheers, KV
What is job scheduler and dispatcher?
No. The Job Scheduler is the high-level scheduler.
Open Source Job Scheduler was created in 2005.
long-term scheduler...
The process of selecting the next job that will run on the CPU belongs to the short-term or CPU scheduler. The CPU scheduler can only pick from the jobs that are already in memory and ready to go. The scheduler works in cooperation with the interrupt system. • The scheduler assigns the CPU to perform computation on behalf of a particular process or thread within a process. • CPU can be "borrowed" from its current process by an interrupt. It is under the control of external devices not scheduler. Interrupts can be disabled for a short time. • When a process or thread requests an I/O transfer, it normally becomes ineligible to use the CPU until the transfer is complete. This means that the scheduler will have to choose a new process or a new thread within the same process to use the CPU. • The process or thread that requested the I/O again becomes eligible to use the CPU when the I/O transfer is complete. CPU I/O Burst Cycle The execution of a process consists of an alternation of CPU bursts and I/O bursts. A process begins and ends with a CPU burst. In between, CPU activity is suspended whenever an I/O operation is needed. • If the CPU bursts are relatively short compared to the I/O bursts, then the process is said to be I/O bound. For example, a typical data processing task involves reading a record, some minimal computation and writing a record. • If CPU bursts are relatively long compared to I/O bursts, a process is said to be CPU bound. A number crunching task involves an I/O burst to read parameters. A very long CPU burst and another I/O burst is required to write results
"Pipelining", in the context of a processor, means that the CPU scheduler creates a specific list of linked instructions (actions) to be fed to the computation units to work. Generally speaking, this list is a series of actions which require the successful completion of the prior one - so, action A completes, then action B takes the output from A and does something, while action C then does something with the output of B, etc.Pipelining can bring significant performance benefits, as each successive action finds all its prerequisites already satisfied, so the action is ready to go immediately.The pipeline is filled by the CPU scheduler from a pool of work which is waiting to occur. Each execution unit has a pipeline associated with it, so as to have work pre-planned.In a non-pipelined CPU, the scheduler merely chooses from the pool of waiting work each time an execution unit signals it is free.Pipelined CPUs are significantly more efficient than non-pipelined CPUs, provided the scheduler can keep the pipeline full. If work on an execution unit produces an output that the scheduler had not predicted (i.e. a jump rather than a computation output), then the pipeline stalls, and it has to be completely emptied, while the scheduler reorders work to account for the new outcome.Thus, the efficiency of a pipelined CPU is entirely dependent on the CPU scheduler's effectiveness at predicting the outcome of each instruction (action). If the workload is such that the predictive scheduler can't do a good job, and frequent pipeline stalls occur, then it will often be the case that a non-pipelined design will perform better on that workload.The tradeoff is thus: the longer the instruction pipeline for an execution unit, the better performance that unit can have, but the harder (and more complex) the work is for the predictive scheduler, and the greater the cost (in terms of performance hit) that a pipeline stall is.
A job scheduler is a software programme that is used for controlling and timing, as well as planning of the background execution of programs. It is used for the automation of programs, scripts and database procedures.
autosys
A job scheduler is a computer program used for controlling background program execution. It is used for programs that that need to run at regular intervals without the need for human intervention.
Long-Term SchedulingLong-term scheduling performs a gatekeeping function. It decides whether there's enough memory, or room, to allow new programs or jobs into the system. It limits the degree of multi-tasking to prevent slow performance on currently-running programs. When a job gets past the long-term scheduler, it's sent on to the medium-term scheduler. Medium-Term SchedulingThe medium-term scheduler makes the decision to send a job on or to sideline it until a more important process is finished. Later, when the computer is less busy or has less important jobs, the medium-term scheduler allows the suspended job to pass. Short-Term SchedulingThe short-term scheduler takes jobs from the "ready" line and gives them the green light to run. It decides which of them can have resources and for how long. The short-term scheduler runs the highest-priority jobs first and must make on-the-spot decisions. For example, when a running process is interrupted and may be changed, the short-term scheduler must recalibrate and give the highest-priority job the green light.