# Logstash JVM heap filling up (dynamic field names)

**URL:** <https://discuss.elastic.co/t/logstash-jvm-heap-filling-up-dynamic-field-names/97334>\
**Category:** Logstash\
**Created:** [August 17, 2017, 4:49am UTC](https://discuss.elastic.co/t/logstash-jvm-heap-filling-up-dynamic-field-names/97334 "2017-08-17T04:49:23Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Exocomp](https://avatars.discourse-cdn.com/v4/letter/e/ea5d25/32.png) [@Exocomp](https://discuss.elastic.co/u/Exocomp)\
**Post date:** [August 17, 2017, 4:49am UTC](https://discuss.elastic.co/t/logstash-jvm-heap-filling-up-dynamic-field-names/97334/1 "2017-08-17T04:49:23Z")

</div>

Here is a summary of what I ran into, hopefully saves someone else some time.

Basically, there is a cache mechanism that logstash uses for string interpolation, there is a bug where random keys (or so it seems at the moment) are added to the cache, in my case there was no limit which ended up filling up the heap. For more info and my work around see the following:

> <https://github.com/elastic/logstash/issues/8019>

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [September 14, 2017, 4:49am UTC](https://discuss.elastic.co/t/logstash-jvm-heap-filling-up-dynamic-field-names/97334/2 "2017-09-14T04:49:29Z")

</div>

Closed on September 14, 2017, 4:49am UTC

This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.