Java Deep Dive — Lesson 3: Profiling, Garbage Collection, and Benchmark Design

Technical Scope

• Java Flight Recorder and Java Mission Control event analysis
• G1, ZGC, pause goals, allocation rate, and collector selection
• CPU, allocation, lock, and I/O profiling with production-safe methods
• JMH warm-up, forks, blackholes, variance, and benchmark interpretation

Instructor Demonstration

The instructor will analyze and reconcile Java Flight Recorder and Java Mission Control event analysis in the context of a latency-sensitive Java service that must remain correct under concurrency, memory pressure, and rolling releases. The demonstration captures commands, configuration, transactions, output, logs, plans, or screenshots that prove both the intended behavior and the control boundary.

Applied Workshop

Learners complete a controlled exercise covering G1, ZGC, pause goals, allocation rate, and collector selection and CPU, allocation, lock, and I/O profiling with production-safe methods, then introduce a realistic exception involving JMH warm-up, forks, blackholes, variance, and benchmark interpretation. They record assumptions, exact steps, expected and observed results, a reversible correction, and the evidence required for operational acceptance.

1. Confirm scope, identities, data, dependencies, controls, and expected result.
2. Perform the product-specific configuration, development, analysis, or business-process task.
3. Capture reproducible technical or transaction evidence and compare it with the expected value.
4. Explain the operational, security, performance, data-quality, or business trade-off.

Validation Standard

Acceptance for Profiling, Garbage Collection, and Benchmark Design requires the result to be reproducible, traceable to approved inputs, consistent with the relevant Oracle or platform behavior, and supported by checks for security, data integrity, reliability, performance, and recoverability.

• The intended target, scope, and ownership are verified.
• Expected-value and negative-path checks pass.
• Security, reliability, performance, data quality, and support impacts are reviewed.
• Unexpected behavior is resolved before acceptance.

Failure Analysis

When the result differs from expectation, learners isolate the smallest proven cause across Java Flight Recorder and Java Mission Control event analysis, G1, ZGC, pause goals, allocation rate, and collector selection, CPU, allocation, lock, and I/O profiling with production-safe methods; they avoid speculative production changes, preserve evidence, apply the lowest-risk correction, rerun the test, and document prevention.

Practical Outcome

Complete and defend a validated result for Profiling, Garbage Collection, and Benchmark Design with a reusable implementation record or runbook.