how to check java heap size in linux

How can I find Java heap size and memory used (Linux)?

stackoverflow.com › questions › 12797560 › how-can-i-find-java-heap-size-and-memory-used-linux

Each Java process has a pid, which you first need to find with the jps command.

Once you have the pid, you can use jstat -gc [insert-pid-here] to find statistics of the behavior of the garbage collected heap.

jstat -gccapacity [insert-pid-here] will present information about memory pool generation and space capabilities.
jstat -gcutil [insert-pid-here] will present the utilization of each generation as a percentage of its capacity. Useful to get an at a glance view of usage.

See jstat docs on Oracle's site.

Answer from farmer1992 on Stack Overflow

Stack Overflow

stackoverflow.com › questions › 12797560 › how-can-i-find-java-heap-size-and-memory-used-linux

How can I find Java heap size and memory used (Linux)? - Stack Overflow

Top answer

1 of 6

Use jps and jstack to learn more about Java processes. jstat can also be useful for Java statistics monitoring.

2 of 6

cd /opt/www/java/jdk/bin/

# jmap -heap <JAVA_PID>

Informatica Knowledge

knowledge.informatica.com › s › article › 588051

Check/Monitor the JAVA HEAP SPACE of a JAVA process

February 28, 2022 - Loading · ×Sorry to interrupt · Refresh

W3Docs

w3docs.com › java

How to find Java Heap Size and Memory Used (Linux)? | W3Docs

To find the Java heap size and the amount of memory used on a Linux system, you can use the jstat command and specify the process ID (PID) of the Java process. ... This will display the Java heap size and the amount of memory used, as well as ...

Quora

ubuntuclub.quora.com › How-to-check-the-Java-heap-size-in-Linux

How to check the Java heap size in Linux - Ubuntu Club - Quora

Quora is a place to gain and share knowledge. It's a platform to ask questions and connect with people who contribute unique insights and quality answers.

Position Is Everything

positioniseverything.net › home › how to check java heap size in linux: a quick guide

How to Check Java Heap Size in Linux: A Quick Guide - Position Is Everything

December 29, 2025 - When working with Java applications ... has enough gas before a long trip. To check the Java heap size in Linux, use commands like ps, jstat, and jcmd....

Mkyong

mkyong.com › home › java › find out your java heap memory size

Find out your Java heap memory size - Mkyong.com

March 9, 2014 - Java heap size InitialHeapSize = 64781184 bytes (61.7M) and MaxHeapSize = 1038090240 bytes (990M). PermGen Size PermSize = 21757952 bytes (20.75M), MaxPermSize = 174063616 bytes (166M) Thread Stack Size ThreadStackSize = 1024 kilobytes (1M) The allocated heap memory size is quite close to the ergonomics result.

Medium

medium.com › @Flashleo › check-and-increase-jvm-heap-size-on-windows-and-linux-machine-bd4e3d0e3b8c

Check and Increase JVM heap size on windows and Linux machine | by Harish K | Medium

August 14, 2020 - Command to find out how much heap size your JVM has: On Windows Machine: Open command prompt and enter below command: java -XX:+PrintFlagsFinal -version | findstr /i “HeapSize PermSize ThreadStackSize” ... To increase the size, I have followed ...

Find elsewhere

Google Bing Mojeek

Codemia

codemia.io › knowledge-hub › path › how_can_i_find_java_heap_size_and_memory_used_linux

How can I find Java heap size and memory used Linux?

Enhance your system design skills with over 120 practice problems, detailed solutions, and hands-on exercises

javathinking

javathinking.com › blog › how-can-i-find-java-heap-size-and-memory-used-linux

How to Check Java Heap Size and Used Memory on Linux via Command Line — javathinking.com

Metaspace (Java 8+): Replaced "PermGen" to store class metadata (not part of the heap but often monitored alongside it). Configured Heap Size: Defined at JVM startup via flags: -Xms: Initial heap size (e.g., -Xms512m = 512 MB). ... Used Heap Size: The actual memory consumed by the application at runtime, which fluctuates as objects are created and garbage-collected. ... A Linux system (e.g., Ubuntu, CentOS) with a Java application running.

CodingTechRoom

codingtechroom.com › question › check-java-heap-size-linux-command-line

How to Check Java Heap Size and Memory Usage in Linux via Command Line? - CodingTechRoom

Use the `jps` command to find the process ID (PID) of your Java application. Use the `jcmd` command to retrieve the heap information for the identified Java process.

UMA Technology

umatechnology.org › home › how to check java heap size and memory usage in linux via command line?

How to Check Java Heap Size and Memory Usage in Linux via Co

To check Java heap size and memory usage in Linux, use jcmd first for effective heap limits (VM.flags) and live heap internals (GC.heap_info).

Red Hat

developers.redhat.com › articles › 2021 › 09 › 09 › how-jvm-uses-and-allocates-memory

How the JVM uses and allocates memory | Red Hat Developer

October 20, 2023 - Many programmers figure out the maximum heap value for their application's JVM correctly but discover that the JVM is using even more memory. The value of the -Xmx parameter specifies the maximum size of the Java heap, but that is not the only ...

Siemens Digital Industries Software

community.sw.siemens.com › s › article › How-do-I-find-the-default-Java-heap-size-for-my-operating-system-on-Linux-or-Windows

How do I find the default Java heap size for my operating ...

January 20, 2023 - Loading · ×Sorry to interrupt · Refresh

Stack Overflow

stackoverflow.com › questions › 9257361 › how-to-check-heap-size-allocated-for-jvm-by-linux › 23253273

tomcat - how to check heap size allocated for jvm by linux - Stack Overflow

Top answer

1 of 4

A simple way on Linux is to run the following:

ps -ef |grep tomcat

Look for the starting and maximum JVM memory:

-Xms1024m -Xmx4096m

In this case it is allocating 1G on startup and the Maximum is 4G.

2 of 4

You can easily check the heap size memory allocation using JConsole, if you have a path to your jre/jdk set up correctly on the system you should be able to start it with command jconsole from anywhere.

For managing your heap memory allocation you can have a look here: http://javahowto.blogspot.com/2006/06/6-common-errors-in-setting-java-heap.html

Unix.com

unix.com › shell programming and scripting

Finding Heap size Command--Urgent - Shell Programming and Scripting - Unix Linux Community

October 18, 2017 - Hi Friends, i need a unix command to check the heap space availability on unix system as I am getting following error: Error occurred during initialization of VM Could not reserve enough space for object heap Error o…

Azul

docs.azul.com › prime › zst › show-heap-sizes

Showing Available Heap Sizes - Azul Docs

[root@localhost bin]# echo "Zing Available Heapsize (MB) is "`zing-ps --acct|grep Committed|awk '{print int($3/(1024*1024))}'` Zing Available Heapsize (MB) is 3854 [root@localhost bin]# echo "Zing Total Heapsize (MB) is "`zing-ps --acct|grep Committed|awk '{print int($4/(1024*1024))}'` Zing Total Heapsize (MB) is 3854 root 5785 java NAME BALANCE ALLOCATED MAXIMUM FND ODFND account[0]: default 10485760 2097152 12582912 0 1 account[1]: emergency_gc 0 0 0 -1 -1 account[2]: heap 555745280 505413632 1283457024 0 1 account[3]: pause_prevention 0 0 274877906944 3 3 account[4]: unknown 0 0 0 -1 -1 acc

Lucee Dev

dev.lucee.org › support

Setting Heap Size (Linux Server) - support - Lucee Dev

January 18, 2024 - I could not find this in the Lucee documentation, so I wanted to check how to properly set the heap size on a Linux server (Ubuntu in my case). Is this the proper procedure: 1. Create setenv.sh file Create a file new named setenv.sh in the following location. sudo nano /opt/lucee/tomcat/bin/setenv.sh 2. Add the JAVA_OPTS line In the file, add JAVA_OPTS line with the desired memory values.

Unix.com

unix.com › unix for beginners q & a › unix for dummies questions & answers

Checking heap memory size for java app - UNIX for Dummies Questions & Answers - Unix Linux Community

July 16, 2010 - Hi I have one Java application installed in my Solaris system. Is there a way to find out the heap memory allocated size/used size/free size for the particular Java process? If anyone knows the command, please let me k…