During performance testing, which tool can be connected to the JVM to monitor CPU usage?

During performance testing, which tool can be connected to the JVM to monitor CPU usage?

• A. Connect VisualGC to the JVM using JMX
• B. SSH into the server and run top
• C. Use jstat to monitor CPU
• D. Use a log parser for performance metrics

Answer: (A)

Monitoring CPU usage from inside the JVM during performance testing works best when you connect a tool to the JVM via JMX. VisualGC, accessed through a JVM connection (like VisualVM), pulls data directly from the JVM’s MBeans, giving you live visibility into GC activity, memory pressure, and related runtime behavior. This direct integration helps you see how the JVM’s internal processes contribute to CPU usage under load, which is exactly what you need during performance testing. Relying on host-level tools like top only shows the whole server’s CPU and isn’t tied to what the JVM is doing. jstat can provide GC and memory stats but isn’t primarily focused on CPU usage, and it isn’t as integrated for real-time, JVM-specific CPU monitoring. A log parser analyzes data after runs rather than providing live metrics during testing.

Monitoring CPU usage from inside the JVM during performance testing works best when you connect a tool to the JVM via JMX. VisualGC, accessed through a JVM connection (like VisualVM), pulls data directly from the JVM’s MBeans, giving you live visibility into GC activity, memory pressure, and related runtime behavior. This direct integration helps you see how the JVM’s internal processes contribute to CPU usage under load, which is exactly what you need during performance testing.

Relying on host-level tools like top only shows the whole server’s CPU and isn’t tied to what the JVM is doing. jstat can provide GC and memory stats but isn’t primarily focused on CPU usage, and it isn’t as integrated for real-time, JVM-specific CPU monitoring. A log parser analyzes data after runs rather than providing live metrics during testing.