Swiss Java Knife

SJK is a command line tool for JVM diagnostic, troubleshooting and profiling.

Starting sjk

java -jar sjk.jar

java -jar sjk.jar --help

Below a few command

ttop

Pools thread CPU usage of target JVM and periodically report to console.

Could sort thread by CPU usage and/or thread's name.
Could limit number of thread displayed

jps

Similar to jps.

Plus could filter process java processes by their system properties.
Plus could display specific system properties of process in output.
Plus could display values of specific -XX for HotSpot JVM processes.

hh

Similar to jmap -histo.

Plus can show histogram of dead objects (histograms of all and live requested, then difference is caluclated).
Plus can show N top buckets in histogram.

gcrep

Report information about GC in real time. Data is retrieved via JMX.

mxdump

Dumps all MBeans of target java process to JSON.