On magnetic disks, files can be organized in one of three ways; ____. The I/O ____ allocates the devices, control units, and channels. A directory of Objective Type Questions covering all the Computer Science subjects.

It is also poorer performance when there is random access of small segments of data, as we need to load the entire block, even though we may olny need a tiny portion of it. A critical region is an area of code where the code expects shared resources not to be changed or viewed by other threads while executing inside the critical region. Once the kernel has control, the user state is saved.

When the system is short of primary memory, the system writes individual pages of some processes to secondary memory but leaves those processes runnable. When a running process, accesses those pages, the process sleeps while the pages are read back into primary memory. A process is sleeping in memory if the process is in primary memory but is waiting for a specific event before continuing execution. For example, a process sleeps while waiting for an I/O operation to complete, for a locked resource to be unlocked, or for a timer to expire. When the event occurs, a wakeup call is sent to the process.

Using the SJN algorithm, the average turnaround time is ___. A jobs working set is the collection of pages that must be loaded from secondary storage. With demand paging, if there are no empty page frames available, to move in a new page, one of the current resident pages must be place into main memory. ___ consists of fragments of free memory between blocks of allocated memory. If the process is intensive in terms of CPU operations then it is called CPU bound process. Similarly, If the process is intensive in terms of I/O operations then it is called IO bound process.

A program is an active entity that requires a set of resources, including a processor and special registers, to perform its function. For Long-term scheduler which of the following stands truei. The long-term scheduler executes much less frequently. At which time it is removed from all queues and has its PCB and resources deallocated. T/F The job of the I/O control unit is to keep up with the I/O requests from the CPU and pass them down the line to the appropriate control unit.

22.In round robin scheduling, if processing isnt finished when time expires, the job is preempted and put at the end of the READY queue and its information is saved in its PCB. 17.If one job monopolizes the system, the extent of its overall effect on system performance depends on the scheduling policy and whether the job is CPU-bound or I/O-bound. 10.From HOLD, the job moves to WAITING when its ready to run but is waiting for the CPU.

Log files (e.g. used for auditing), append-only prevents modifying any existing log entries. Give an example of a scenario that might benefit from a file system supporting an append-only access write. Filesystems can support sparse un65ju670dfxza reviews files, what does this mean? Give an example of an application’s file organisation that might benefit from a file system’s sparse file support. What is a test-and-set instruction? How can it be used to implement mutual exclusion?