What is your experience in testing and optimizing high-traffic systems?

In the field of testing and optimization of high-traffic systems, I have worked with load testing and performance profiling.

Main approaches:

• Using load testing tools (e.g., JMeter, Locust) to simulate a large number of users and identify bottlenecks.
• Analyzing metrics such as CPU, memory, delays, and throughput.
• Code and architecture optimization: caching, asynchronous processing, reducing locks.
• Horizontal scaling: adding servers, load balancing.
• Using profilers (e.g., Visual Studio Profiler for C#) to find "hot" spots.

Example: during testing a web service under load, I identified that the bottleneck was a synchronous call to the database. I moved part of the logic to asynchronous calls and implemented caching, which reduced response time and increased throughput.