README.md

EProfiler

Configuration

Profiler parameters are passed through command line, separated by ;.
Parameters that have key and value are separated by =. For example
-javaagent:eprofiler.jar=classPattern=org.example.*;outputFolder=path/to/logs;debug;showBytecode;minDurationToLog=10

List of parameters

• outputFolder - required, path to the folder, where logs will be stored
• classPattern - required, only classes that matches specified patterns will be profiled, multiple patterns may be defined (e.g. classPattern=org.example.*;classPattern=org.another.example.*;)
• debug - log debug information, default is false
• showBytecode - log bytecode of instrumented classes
• minDurationToLog - only methods which took longer than specified time (in milliseconds) will be logged. If method takes less, it's time is added to it's parent time.

How to run

On tomcat

Create the file PATH_TO_APACHE/bin/setenv.bat (or setenv.sh for Linux) if missing and add

set CATALINA_OPTS="-javaagent:path/to/eprofiler.jar=args"

In JUnit

Java Attach API can be used to instrument the classes at runtime. To use it, you must have tools.jar on your classpath.

To add tools.jar in maven, add it to your pom:

<dependency>
  <groupId>com.sun</groupId>
  <artifactId>tools</artifactId>
  <version>1.7</version>
  <scope>system</scope>
  <systemPath>${java.home}/../lib/tools.jar</systemPath>
</dependency>

To use Attach API add this before your tests (for example in static code block)

try {
    VirtualMachine vm = VirtualMachine.attach(vmPid);
    vm.loadAgent("path\\to\\eprofiler.jar", "args");
    vm.detach();
} catch (Exception e) {
    throw new RuntimeException(e);
}

You can get vm process pid this way

String nameOfRunningVM = ManagementFactory.getRuntimeMXBean().getName();
int p = nameOfRunningVM.indexOf('@');
String pid = nameOfRunningVM.substring(0, p);