bottleneck
A phase in a program's execution that significantly slows down the performance of the entire program. Common causes for bottlenecks include:
§ Useless computation, such as sorting a list before knowing whether the user even wants the list displayed
§ Needless recomputation, such as recomputing the same value instead of caching the results the first time
§ Excessive requests for services, such as processing many small operating system requests instead of a few large ones
§ Waiting for services to complete, such as calling waiting and blocking functions, procedures, or methods (for example, SendMessage() or EnterCriticalSection())
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