Java containers in production - Mastering the "banana box principle"

• Slides for the 50 min talk click here

© skretch notes https://github.com/corinnekrych

• This repository was used to accompany the talk with a demo for the developer conference session : 2018.rivieradev.fr/session/338 (NCE, France)

This repository allows you to quickly create a fat jar only using JDK features (no Maven, no gradle, no depedencies like Spring-Boot). Once the jar compiled it is used to be mounted into a docker container of your choice, see demo-source-script-talk. Goal is to quickly validate JVM behavior on containers using different versions of JDK (JDK8, 9, 10, 11,...).

Prerequisites

You need to be root on the machine or have extended sudo rights.

You need install some extra packages. On an RPM-based Linux box you can simply use :

• sudo yum install -y docker && sudo systemctl start docker (make sure you use docker 1.13 as in previous versions you can not start a deamon container with the --rm option)
• sudo yum install -y java-1.8.0-openjdk-devel
• sudo yum install -y stress Optional is the installation of command line tool stress, allowing to demo an RAM intensive application, see usage in demo-source-script-talk.
• sudo yum install -y dstat Optional is the installation of command line tool dstat used for resource monitoring, see usage in demo-source-script-talk.

Furthermore you should disabled the swap as mentioned in the talk : sudo swapoff -a

Build and validate BananaServer.jar

This very simple BananaServer has been derived from : https://github.com/kanedafromparisfriends/resourcesmonger

$ cd ${YOUR_GIT_CLONE}
$ cd java-application-server-fat-jar
$ ./build-and-run.sh
added manifest
adding: fr/(in = 0) (out= 0)(stored 0%)
adding: fr/rivieradev/(in = 0) (out= 0)(stored 0%)
adding: fr/rivieradev/BananaServer$KRootHandler.class(in = 4976) (out= 2644)(deflated 46%)
adding: fr/rivieradev/BananaServer.class(in = 2628) (out= 1444)(deflated 45%)
adding: fr/rivieradev/_2018/(in = 0) (out= 0)(stored 0%)
adding: fr/rivieradev/_2018/_338/(in = 0) (out= 0)(stored 0%)
adding: fr/rivieradev/_2018/_338/BananaServer$KRootHandler.class(in = 5009) (out= 2658)(deflated 46%)
adding: fr/rivieradev/_2018/_338/BananaServer.class(in = 2650) (out= 1459)(deflated 44%)
Main Class Start

Exit by Ctrl+C

Link previously build BananaServer to container image & run the Banana Box container

$ cd ${YOUR_GIT_CLONE}
$ source demo-source-script-talk
# now type run- && use TAB for autocompletion
$ run-

Now you run any container that has been preconfigured (the demo scripts used during the presentation are called run-<DEMO-ID>-x.y.z). You will need an internet connection to pull down the base images referenced.

$ cd ${YOUR_GIT_CLONE}
$ source demo-source-script-talk
$ run-1-chaos-monkey-mem-consumer-app
$ run-1-openjdk8-fat-jar-no-limits-best-effort
$ run-2- ....

As in some cases a container is started in the background in a non-interactive way you can easily kill all containers on your box using

$ cd ${YOUR_GIT_CLONE}
$ source demo-source-script-talk
$ dk