Increasing Java Heap size for docker container

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Hi, Has anyone tried increasing Java Heap size in Docker container to run the docker image generated for mendix application? Any help on this would be appreciated. Thanks!
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1 answers
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When deploying Mendix in Dockers, it is my experience that you will need to refer to the documentation frequently, both the docker-mendix-buildpack and the cf-mendix-buildpack.

The latter one contains the way to set the heap size for a Docker using an environment variable:

HEAP_SIZE 512M

[edit]

You set this environment variable the same way you set any environment variable. At my client, we have a fully customized setup, my code example won't help, but the documentation shows the following example to set environment variables when running your Docker:

docker run -it \
  -e ADMIN_PASSWORD=Password1! \
  -e DATABASE_ENDPOINT=postgres://username:password@host:port/mendix \
  mendix/mendix-buildpack:v1.2

Adding the heap size to this, it would look like:

docker run -it \
  -e ADMIN_PASSWORD=Password1! \
  -e DATABASE_ENDPOINT=postgres://username:password@host:port/mendix \
  -e HEAP_SIZE=1024M \
  mendix/mendix-buildpack:v1.2

Finally, having looked at my code, I actually use two environment variable to control heap size: HEAP_SIZE and MEMORY_LIMIT. HEAP_SIZE is set to 90% of MEMORY_LIMIT (so, for a Docker with 1GB memory, we use MEMORY_LIMIT=1024M and HEAP_SIZE=920M). I didn't find that in the documentation, but it is in the Python code of the cf-mendix-buildpack. So, the final configuration we end up with looks like this:

docker run -it \
  -e ADMIN_PASSWORD=Password1! \
  -e DATABASE_URL=sqlserver://username:password@host:port/mendix \
  -e MEMORY_LIMIT=1024M \
  -e HEAP_SIZE=920M \
  mendix/mendix-buildpack:v1.2

 

 

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