java_tool

ps -ef | grep 'java'
jmap -dump:format=b,file=/home/work/jvmDmp.hprof [pid]
jmap -dump:live,format=b,file=/home/work/jvmDmp.hprof [pid]
jmap -histo:live 2253 | more
jmap -histo 2378 | more
jstack [pid]
jstack 2378 | more
jmap -histo:live 2378 | more 

jps jinfo jstat jmap jstack

dmesg