Useful Java tools to try

java mission control - to monitor jvm

lincheck - testing concurrent data structures

jmh - it is tool for microbenchmarking your code

debezium - tool to capture database changes (mongo, oracle...)

JVM benchmark example

A JVM benchmark example from real project (QuickFIX/J is library that implements finacial FIX protocol) https://github.com/quickfix-j/quickfixj/wiki/JMH-benchmark-for-%2339-and-%2342

JVM Language Summit 2016

https://www.youtube.com/playlist?list=PLX8CzqL3ArzUY6rQAQTwI_jKvqJxrRrP_

JVM Performance Tuning

while(iAmNotSatisfied){  
   size = defineMinMaxHeapSize();
   ratios =  tuneGenerationRatios();
   alg = selectAppropriateGcAlgorithm();
   testApplication(size, ratios, alg);
   iAmNotSatisfied = analyzeStatistics();
}
More details later...;)

References:
From Vladislav Gangan Software as Craft presentation
Books:
Java Performance Tuning (2nd Edition)
Pro Java EE 5 Performance Management and Optimization
Java Performance

Java HotSpot VM Options