Scouter is an open source APM (Application Performance Management) tool.

scouter2-prototyping

Zikpin Scouter UDP storage and other zipkin-scouter integrations.

scouter demo system and test beds

scouter c++ library

SCOUTER Server Plugin sample (null plugin)

Bytescope is light-weight CLI tool for tracing JVM runtime code. (measure servlet response time, thread status, checking method argument, return values and anything you want to by runtime scripting injection)