Insight is a Java agent for automatically aggregating request metrics from a Servlet 3.0 based web container. For each request, we track the request time, the number of Strings allocated as well as the total memory allocated. It hooks into the web application runtime by injecting a special tracking filter into each ServletContext.
The individual requests as well as aggregate data can be viewed at localhost:8081/index.html.
The Java Agent can be used attached to a web application on the command line as follows:
java -javaagent path/to/insight-agent.jarBy default, the agent will launch a web server for metrics browsing on port 8081. To modify the port, pass it as an agent argument:
java -javaagent path/to/insight-agent.jar=port:{your_port}Checkout the source code and run from the root:
gradlew build
The compiled agent jar file will be found under ./agent/build/libs/insight-agent.jar
To run a super simple demo, checkout the source code and run from the root:
gradlew demo
Navigate your browser to localhost:8081/index.html where the Insight UI will be running. To generate sample http requests, browse to localhost:8080/test
- Only tested with Spring Boot, Jetty and Tomcat.
- Only tracks allocations made by the requesting thread, not child threads.
- Request history is not persistant and only the 1000 most recent requests are tracked in memory. Future implementations may include a persistance implementation.
This agent relies on Google's Allocation Instrumenter to track String object creation as well as Memory allocation. Thanks Google!