Here's a free checklist of load testing metrics to measure when evaluating your application's performance:

• 1. Web Server Metrics
  • Busy and idle threads - Do you need more web servers or works?
  • Throughput - How many transactions per second can you handle?
  • Bandwidth Requirements - Is the network creating a bottleneck?

• 2. App Server Metrics
  • Load distribution - Do you need more application servers?
  • CPU usage - How much CPU usage do you need for each load?
  • Memory usage - Are there any memory leaks?
  • Worker threads - Are workers correctly configured?

• 3. Host Metrics
  • CPU, memory, disk - Are there problems with network interfaces?
  • Key processes - What processes are running on the host?

• 4. App Metrics
  • Time spent in logic layer - What layer slows down with an increased load?
  • Number of calls in logic layer - How often are you calling internal web services?

• 5. API Metrics
  • ​Transactions per second - How much throughput can you handle?
  • Bits per second - Is data a bottleneck?