Primary Meaning: A scheduling anomaly in which a process or thread is perpetually denied access to necessary system resources (e.g., CPU time, memory, I/O devices) due to the priority-based or resource allocation policies of the operating system. As a result, the task cannot proceed with execution indefinitely, even though it is in a ready state.
Definition: A condition where a lower-priority process is continuously preempted by higher-priority processes, or a task is excluded from resource allocation for an extended period because the scheduler prioritizes other tasks. Starvation typically arises in systems with static priority scheduling and lacks mechanisms for fair resource distribution.
Example 1: In a real-time operating system (RTOS) with fixed-priority scheduling, if high-priority tasks arrive continuously, low-priority tasks may never get a chance to execute, leading to starvation.
Example 2: When multiple processes compete for a limited number of printer devices, a process that submits print requests later might be starved if the scheduler always assigns the printer to earlier requests without a fairness mechanism.
2. Common Causes of Starvation
Static Priority SchedulingProcesses are assigned fixed priorities, and higher-priority tasks always preempt lower-priority ones. If high-priority tasks are generated continuously, lower-priority tasks will be starved.
Resource Leakage or MonopolizationA process holds a critical resource for an excessive duration without releasing it, preventing other processes from accessing the resource and causing starvation.
Lack of Fairness MechanismsThe scheduling algorithm does not include policies like aging to adjust task priorities dynamically, leading to long-term resource exclusion for certain tasks.
3. Solutions to Starvation
AgingA dynamic priority adjustment technique where the priority of a waiting process increases gradually over time. Eventually, the process’s priority will rise high enough to gain access to the required resources.
Fair Share SchedulingThe scheduler allocates system resources proportionally among all processes or user groups, ensuring that each task gets a fair share of resources instead of being dominated by high-priority tasks.
Resource Queuing with Time LimitsSet a maximum waiting time for processes in resource request queues; if a process exceeds the limit, it is prioritized for resource allocation to avoid indefinite waiting.
4. Common Collocations
English Collocation
Chinese Translation
Process starvation
进程饥饿
Resource starvation
资源饥饿
Starvation avoidance
饥饿避免
Starvation vs. Deadlock
饥饿与死锁
Aging mechanism for starvation prevention
防止饥饿的老化机制
5. Key Distinction: Starvation vs. Deadlock
Feature
Starvation
Deadlock
Task State
At least one process is in the ready state, waiting for resources
All involved processes are in a blocked state, waiting for resources held by each other
Resource Dependency
No circular wait; caused by unfair resource allocation
Caused by circular wait of resources, along with mutual exclusion, hold-and-wait, and no-preemption
Resolvability
Can be resolved by adjusting scheduling policies (e.g., aging)
Requires external intervention (e.g., resource preemption, process termination) to resolve
Occurrence Scope
Affects individual processes or a subset of processes
Affects all processes involved in the circular wait
Ruigu Electronic 
Leave a comment