Some systems use a strategy known as ____ to increase the priority of jobs that have been in the system for an unusually long time in order to expedite their exit. If all processes I/O bound, the ready queue will almost always be ______, and the Short term Scheduler will have a ______ to do. If all processes I/O bound, the ready queue will almost always be ______ and the Short term Scheduler will have a ______ to do. 4.The Process Scheduler assigns the CPU to execute the processes of those jobs placed on the ____ queue by the Job Scheduler.

Otherwise, display the message ‘No Ruby’. When a job is accepted by the system, it’s put on ____ and placed in a queue. Web browsers use multithreading routinely. For example, one thread can retrieve images while another sends and retrieves e-mail.

But in reality, only one task is being executed at a particular instant of time by a processor. Here, the context switching is so fast that the user feels that the CPU is executing more than one task at the same time. Preemptive scheduling menas that processes are context switched at regular time intervals, tug job movie by the kernel. Non pre-emptive scheduling, means a process returns control to other processes upon termination, or by yielding . Fair share of cpu-time in a non-preemptive system requires that all processes are yielding at similar time intervals. A single process can monopolise cpu time by not yielding.

Too much buffering in really high speed networks can reduce performance, if the time required to copy between buffers is comparable to the time spent acting on data. 2) Least Recently Used – calculate whatever page hasn’t been used the longest, and boot it. Impossible to implement efficiently in practice – requires a timestamp on every memory reference. If the page size is small, the work set size is smaller as the pages more accurately reflect current memory usage (i.e. there is less unrelated data within the page). 2-level page table is slower to look up as it requires 2 memory references per lookup. External devices have no guarantee of connectivity.

The printer needs all of a jobs output before it will begin printing, but the spooling system fills the available disk space with only partially completed output. A ___ is created by a process, and it can be scheduled and executed independently of its parent process. The OS maintains all PCBs in Process Scheduling Queues. The OS maintains a separate queue for each of the process states and PCBs of all processes in the same execution state are placed in the same queue. When the state of a process is changed, its PCB is unlinked from its current queue and moved to its new state queue. ____ is the policy of allowing only one process to have access to a dedicated resource.

A process control block is a data structure used by computer operating systems to store all the information about a process. It is also known as a process descriptor. When a process is created , the operating system creates a corresponding process control block. Thrashing occurs when too many processes are run on a processor at a given time. What occurs is the the number of page faults increase dramatically and the virtual memory subsystem is constantly paging pages in and out of memory. This occurs when the working set of all processes is larger than the amount of RAM available on a system.