Introducing MyPerf4J: A High‑Performance Java Monitoring and Statistics Tool

In response to growing service scale and the limitations of vertical architectures, a company adopted a service‑oriented approach and needed a way to observe each service’s runtime characteristics such as QPS, latency percentiles, load balance, and resource usage.

Background

The shift to micro‑services introduced challenges: unknown per‑service QPS, latency distribution, bottleneck identification, load balancing, and capacity planning.

Use Cases

Rapidly locate performance bottlenecks in a Java application during development.

Continuously monitor performance indicators of Java applications in production.

Key Features

High Performance: Single‑threaded recording supports up to 10 million records per second, each taking only 73 ns.

Non‑Intrusive: Integrated via a JavaAgent, requiring no code changes.

Low Memory Footprint: Uses object reuse to minimize temporary allocations and GC impact.

High Precision: Measures response time in nanoseconds.

Real‑Time: Provides second‑level monitoring (minimum 1 s interval).

Monitoring Metrics

MyPerf4J collects dozens of metrics in real time, grouped by category:

Method

RPS, Count, Avg, Min, Max, StdDev, TP50, TP90, TP95, TP99, TP999, TP9999, TP99999, TP100

Memory

HeapInit, HeapUsed, HeapCommitted, HeapMax, NonHeapInit, NonHeapUsed, NonHeapCommitted, NonHeapMax

JVM GC

CollectCount, CollectTime

JVM Class

Total, Loaded, Unloaded

Quick Start

MyPerf4J is delivered as a JavaAgent JAR. To begin:

Download and unzip MyPerf4J-ASM.zip .

Read the extracted README file.

Edit MyPerf4J.properties to set app_name , metrics.log.xxx and filter.packages.include .

Configuration

Add the following JVM arguments:

-javaagent:/path/to/MyPerf4J-ASM.jar
-DMyPerf4JPropFile=/path/to/MyPerf4J.properties

Run

Start the application; metrics are written to /path/to/log/method_metrics.log in a CSV‑like format, e.g.:

MyPerf4J Method Metrics [2020-01-01 12:49:57, 2020-01-01 12:49:58]
Method[6]    Type    Level   TimePercent   RPS   Avg(ms)   Min(ms)   Max(ms)   StdDev   Count   TP50   TP90   TP95   TP99   TP999   TP9999
DemoServiceImpl.getId2(long)   General   Service   322.50%   6524   0.49   0   1   0.50   6524   0   1   1   1   1   1   1
...

Uninstall

Remove the two JVM arguments and restart the JVM.

Open‑Source Repository

The project is hosted at https://github.com/LinShunKang/MyPerf4J .

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