Thrashing occurs when a computer's physical memory (RAM) is overcommitted or insufficient to hold the working sets of all running processes. This causes the operating system to spend most of its time swapping pages of data between RAM and disk (virtual memory) rather than executing actual processes, resulting in severe performance degradation.
Key Points on When Thrashing Occurs
- It happens when the demand for memory exceeds the available physical RAM, forcing the system into constant paging or swapping.
- Processes frequently access memory pages not currently in RAM, causing repeated page faults and heavy disk activity.
- Thrashing typically occurs under a high degree of multiprogramming when many processes compete for limited memory.
- The system spends more time managing memory transfers than performing productive work, slowing down overall performance drastically.
This phenomenon is especially common in multitasking environments where running too many processes or memory-intensive applications overwhelms the available memory resources.
