Resource starvation
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In computer science, starvation is a multitasking-related problem, where a process is perpetually denied necessary resources. Without those resources, the program can never finish its task.
Starvation is similar in effect to deadlock. Deadlock occurs when two programs each hold resources the other needs to finish, and neither is willing to give them up. Starvation occurs when one program holds resources the other needs, but is unwilling to give them up.
Starvation is illustrated by Edsger Dijkstra's dining philosophers problem.
The fault lies in the scheduling algorithm. The scheduling algorithm, which is part of the kernel, is supposed to allocate resources equitably; that is, the algorithm should allocate resources so that no process perpetually lacks necessary resources.
Many operating system schedulers have the concept of process priority. A high priority process A will run before a low priority process B. If the high priority process (process A) never blocks, the low priority process (B) will (in some systems) never be scheduled - it will experience starvation. If there is an even higher priority process X, which is dependent on a result from process B, then process X might never finish, even though it is the most important process in the system. This condition is called a priority inversion. Modern scheduling algorithms normally contain code to guarantee that all processes will receive a minimum amount of each important resource (most often CPU time) in order to avoid any process from being subjected to starvation.
In computer networks, especially wireless networks, scheduling algorithms may suffer from scheduling starvation. An example is maximum throughput scheduling.
