.NET Architecture & System Design Interview Question #140

What is concurrency limiting?

Resilience, Rate Limiting, Health Checks & Observability Senior Advanced

Quick Interview Answer

Concurrency limiting restricts the number of operations executing at the same time rather than the number started during a time window.

Detailed Explanation

Concurrency limiting restricts the number of operations executing at the same time rather than the number started during a time window.

It is useful for protecting scarce resources such as database connections, CPU-intensive work, or downstream dependencies. Excess requests can wait in a bounded queue or be rejected.

Code Example

Maximum active requests = 50

Active: 50
New request
 -> bounded queue
 or reject