How to use jmap heap

Question

I have seen in tutorials, that with command jmap -heap<pid>, I can receive info about heap state.

Now this command is unavailable.

There are only jmap -dump:live,format:b,file=heap.bin but it save data to unreadable bin format.

How can I receive heap state info using jmap to console?

*On Windows

Upd. I found the answer: On new versions Jdk we can use command:

jhsdb jmap --heap --pid

Are you running it on Unix platform ? – Steephen Dec 10 '20 at 06:51 — Steephen, Dec 10 '20 at 06:51
No, on Windows. – Егор Гераськин Dec 10 '20 at 08:17 — Егор Гераськин, Dec 10 '20 at 08:17

score 1 · Accepted Answer · answered Dec 10 '20 at 10:05

1

I found the answer. In new JDK versions it works:

jhsdb jmap --heap --pid <pid number>

answered Dec 10 '20 at 10:05

Егор Гераськин

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score 0 · Answer 2 · answered Dec 10 '20 at 06:54

If you are running on a Unix/Linux platform execute following command to generate the heap dump.

kill -3 <PID of the Java Process>

Generated heap dump file will be either in home directory of the user executed the command, or in absolute path of the jar file.

leonardkraemer · Answer 3 · 2020-12-10T08:40:05.687

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You can analyze the heapdump generated by jmap -dump:live,format:b,file=heap.bin with https://www.eclipse.org/mat/. MAT is able to read the binary format.

edited Dec 10 '20 at 08:40

answered Dec 10 '20 at 07:50

leonardkraemer

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I use IntellijIDEA – Егор Гераськин Dec 10 '20 at 08:39
I highly recommend MAT see also https://stackoverflow.com/questions/26460410/how-can-i-analyze-a-heap-dump-in-intellij-memory-leak for more options – leonardkraemer Dec 10 '20 at 08:41
MAT is available as a standalone application, you don't have to use eclipse as IDE – leonardkraemer Dec 10 '20 at 08:43

How to use jmap heap

jhsdb jmap --heap --pid

3 Answers3