# Why heap memory used is less than Xms

**URL:** <https://forum.inductiveautomation.com/t/why-heap-memory-used-is-less-than-xms/94654>\
**Category:** General Discussion\
**Created:** [August 14, 2024, 2:44pm UTC](https://forum.inductiveautomation.com/t/why-heap-memory-used-is-less-than-xms/94654 "2024-08-14T14:44:15Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![bab\_bab](https://avatars.discourse-cdn.com/v4/letter/b/dec6dc/32.png) [@bab\_bab](https://forum.inductiveautomation.com/u/bab_bab)\
**Post date:** [August 14, 2024, 2:44pm UTC](https://forum.inductiveautomation.com/t/why-heap-memory-used-is-less-than-xms/94654/1 "2024-08-14T14:44:15Z")

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I have set Xms = 3G and Xmm= 10G but it is showing heap used less than 3G.  
That is strange . Why it is happening ?

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**Author:** ![kcollins](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kcollins/32/19646_2.png) [@kcollins](https://forum.inductiveautomation.com/u/kcollins)\
**Post date:** [August 14, 2024, 2:58pm UTC](https://forum.inductiveautomation.com/t/why-heap-memory-used-is-less-than-xms/94654/2 "2024-08-14T14:58:40Z")

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How are you configuring the memory settings? If you're wanting to drive `-Xms` and `-Xmx` directly, you may need to disable the Java service wrapper settings that might be overriding you.

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**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [August 14, 2024, 4:21pm UTC](https://forum.inductiveautomation.com/t/why-heap-memory-used-is-less-than-xms/94654/3 "2024-08-14T16:21:33Z")

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Those settings tell java how much heap memory to **set up** , by allocating from the OS. How much heap is **used** varies as the java application runs. What are you expecting?

Keep in mind that Ignition generates those actual JVM settings from `ignition.conf`. In production, the min and the max should be set the same.

(Perhaps show a screenshot of your Ignition Status =\> Performance page.)

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<div class="post-metadata">

**Author:** ![bab\_bab](https://avatars.discourse-cdn.com/v4/letter/b/dec6dc/32.png) [@bab\_bab](https://forum.inductiveautomation.com/u/bab_bab)\
**Post date:** [August 15, 2024, 2:53pm UTC](https://forum.inductiveautomation.com/t/why-heap-memory-used-is-less-than-xms/94654/4 "2024-08-15T14:53:19Z")

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I am really confused . please follow my configuration in standalone.conf

```python
JAVA_OPTS="-Xms3g -Xmx10g -XX:MetaspaceSize=1024M -XX:MaxMetaspaceSize=4096m -Djava.net.preferIPv4Stack=true -d64 -XX:+HeapDumpOnOutOfMemoryError -XX:+UseG1GC -XX:+UseStringDeduplication"
   JAVA_OPTS="$JAVA_OPTS -Djboss.modules.system.pkgs=$JBOSS_MODULES_SYSTEM_PKGS -Djava.awt.headless=true"

```

As you can see I set Xms3g but due monitoring by jvmconsole or other tools always it is showing memory used is less thatn 3G . Why ? Is that correct while I was set Xms3 ?

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<div class="post-metadata">

**Author:** ![kcollins](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kcollins/32/19646_2.png) [@kcollins](https://forum.inductiveautomation.com/u/kcollins)\
**Post date:** [August 15, 2024, 3:53pm UTC](https://forum.inductiveautomation.com/t/why-heap-memory-used-is-less-than-xms/94654/5 "2024-08-15T15:53:53Z")

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Keep in mind that this forum is for Inductive Automation's [Ignition](https://inductiveautomation.com/ignition/) platform, not Ignition for Fedora CoreOS, which is something completely different; we can't help you much with that.