Search results
Results from the WOW.Com Content Network
A "ready" or "waiting" process has been loaded into main memory and is awaiting execution on a CPU (to be context switched onto the CPU by the dispatcher, or short-term scheduler). There may be many "ready" processes at any one point of the system's execution—for example, in a one-processor system, only one process can be executing at any one ...
A wait state is a delay experienced by a computer processor when accessing external memory or another device that is slow to respond. Computer microprocessors generally run much faster than the computer's other subsystems, which hold the data the CPU reads and writes.
When a process is created (initialized or installed), the operating system creates a corresponding process control block, which specifies and tracks the process state (i.e. new, ready, running, waiting or terminated). Since it is used to track process information, the PCB plays a key role in context switching. [1]
minimizing wait time (time from work becoming ready until the first point it begins execution); minimizing latency or response time (time from work becoming ready until it is finished in case of batch activity, [1] [2] [3] or until the system responds and hands the first output to the user in case of interactive activity); [4]
At this point, the CPU sits idle. The CPU-bound process will then move back to the ready queue and be allocated the CPU. Again, all the I/O processes end up waiting in the ready queue until the CPU-bound process is done. There is a convoy effect as all the other processes wait for the one big process to get off the CPU. This effect results in ...
Once the event occurs for which the process is waiting ("is blocked on"), the process is advanced from blocked state to an imminent one, such as runnable. In a multitasking computer system, individual tasks, or threads of execution, must share the resources of the system. Shared resources include: the CPU, network and network interfaces, memory ...
A process that is ready to run but waiting for the CPU can be considered blocked. A priority scheduling algorithm can leave some low-priority processes waiting indefinitely. A steady stream of higher-priority processes can prevent a low-priority process from ever getting the CPU. [1]
For the portion of the time required for CPU cycles, the process is being executed and is occupying the CPU. During the time required for I/O cycles, the process is not using the processor. Instead, it is either waiting to perform Input/Output, or is actually performing Input/Output. An example of this is reading from or writing to a file on disk.