The situation where the processor spends most of its time swapping process pieces rather than executing instructions is called .

The situation you're describing is called "thrashing."

Thrashing occurs when a system is overwhelmed with too many processes competing for limited resources, particularly memory. In this scenario, the operating system spends an excessive amount of time swapping data between the main memory (RAM) and secondary storage (such as a hard drive or SSD), rather than executing the actual processes. This swapping typically happens because the system does not have enough physical memory to accommodate all the active processes, leading to constant loading and unloading of process pieces (or pages).

As a result, the system becomes inefficient, and overall performance deteriorates, as the CPU remains idle for significant periods while waiting for the memory management to complete. Effective memory management, including adequate swapping strategies, is crucial in preventing thrashing and ensuring that processes can execute smoothly and efficiently.

To mitigate thrashing, system administrators might increase the physical memory, reduce the number of concurrent processes, or optimize resource allocation to ensure that the most critical processes have enough memory to operate effectively.