Throughput

Definition

The actual amount of data that is successfully transmitted over a network or processed by a system in a given time period.

What Problem It Solves

Throughput measures the actual, real-world rate of successful data processing and delivery under load. It solves performance opacity by showing whether system hardware (bandwidth) is being bottlenecked by software issues (such as slow CPU, database locks, or disk write limits).

What Happens If Not Used

Without measuring throughput, developers might scale network bandwidth in vain, failing to identify that software processing bottlenecks are the true cause of slow page loads or API request queues.

Easy Wording

The actual amount of traffic passing through the pipe. While bandwidth is the limit of what could flow, throughput is how much actually flows.

Layman Example

Even if a highway has 6 lanes (high bandwidth), if there is a traffic jam, construction, or bad weather, only 10 cars per minute might pass a checkpoint. Those 10 cars per minute are the throughput.

Technical Example

An API endpoint might have a server network card with 10 Gbps bandwidth. However, due to database locks and CPU usage, the system can only process 100 requests per second, delivering an actual throughput of 5 MB/s. We measure throughput under load using performance testing tools like autocannon or k6.