Bottleneck

A bottleneck is a point in a system where limited capacity slows the overall flow of work. It is the component with the smallest effective throughput that constrains the rate at which outputs are produced. In manufacturing, bottlenecks often occur at the slowest operation in a production line, where longer cycle times cause work-in-progress to accumulate and extend lead times. Problems at a bottleneck can ripple through the operation, causing downstream processes to wait and upstream processes to pile up.

In computing and information systems, bottlenecks arise when a resource cannot sustain required data rates. Common culprits include CPU processing power, memory bandwidth, storage input/output, and network capacity. Identifying the bottleneck typically requires profiling and measurement; optimization targets the constrained resource to improve overall system performance, possibly by parallelization, caching, or hardware upgrades.

In networks, bottlenecks occur when link capacity or congestion limits data transfer, increasing latency and potentially causing packet loss. In project management and operations research, the bottleneck refers to the constraint that caps system output; the Theory of Constraints encourages elevating the bottleneck’s capacity or reworking the process to remove it.

Mitigation strategies include increasing the bottleneck’s capacity, redistributing workload, reducing non-value-added steps, improving scheduling, and adding buffers to smooth flow. The objective is to raise overall throughput while avoiding overinvestment or diminishing returns.