DocumentationAPICommunitySupport

JVM in a Kubernetes Container

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If you're attaching the OverOps Micro-Agent to an environment that's running Java 10 or 11 or any IBM Java version, please follow these guidelines:

When attaching an OverOps Agent to a JVM that is running Java 10 or 11 or any IBM java versions, follow these guidelines:

  1. Turn off Class Sharing: This can be done using the following flags:
    for IBM Java
    ‑Xshareclasses:none
    for HotSpot
    -Xshare:off -XX:-UseTypeSpeculation

  2. Increase ReservedCodeCache to at least 512mb by adding the following flag
    -XX:ReservedCodeCacheSize=512m

  3. The Agent should appear last in the VM arguments list before specifying the main class or jar.

  4. When adding/removing 3rd party packages, the Agent should be restarted.

Additionally, if you wish to upgrade your own compiler to target Java 10/11, then you'll have to upgrade your Collector (SaaS) or Collector + backend (On-Premises) to support it.

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AIX - Statistic Overhead and Performance

When running on an AIX system please add the following parameter to reduce the Statistics Overhead and increase performance
-Dtakipi.neo.heapless.inst.pre.vm=path/to/java-executable
Details can be found in the Micro-Agent Properties

For example path: ../jre/bin/java binary

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Agent Ranking

Make sure that the OverOps Micro-Agent is the last -agentlib or -agentpath argument in your argument list if you are using any other agents with your application in addition to OverOps.

Attaching the OverOps Micro-Agent to Containers in Kubernetes

The OverOps Micro-Agent library can be made available to a container through a Persistent Volume or by copying it directly into an image.

Set environment variables to configure the Agent to connect to the Collector and to attach the Micro-Agent to all running JVMs inside the container.

TAKIPI_COLLECTOR_HOST=collector
TAKIPI_COLLECTOR_PORT=6060
JAVA_TOOL_OPTIONS=-agentpath:/takipi/lib/libTakipiAgent.so

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Note

If you're running more than one JVM inside a container and you do not want OverOps to monitor all of them, you'll need to modify the command used to start your JVM.

Instead of setting the JAVA_TOOL_OPTIONS environment variable, start your JVM with
-agentpath:/takipi/lib/libTakipiAgent.so before the -jar and -cp arguments.

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Tip

For best results, name your applications and deployments at the JVM level.
see Naming the Application, Server, Deployment for details.

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Agent Ranking

Make sure that the OverOps agent is the last -agentlib or -agentpath argument in your argument list if you are using any other agents with your application in addition to OverOps.

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Note

Verify that the -Dtakipi.* JVM arguments are located before the -jar and -cp arguments.

The OverOps Micro-Agent is a native agent and is OS-specific. If using an:

  • Alpine Linux based image, use the Alpine Agent
  • Red Hat and Debian based images, use the Standard Agent.

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Important

Are you seeing this error?
Error relocating libHSAgent.so: __strtod_internal: symbol not found

Persistent Volume

The Micro-Agent can be stored on a persistent volume and mounted into a container at runtime by adding the following to your pod or deployment controller's container spec, modified to use your volume:

  env:
	- name: TAKIPI_COLLECTOR_HOST
  	  value: "overops-collector-service"
	- name: TAKIPI_COLLECTOR_PORT
  	  value: "6060"
	- name: TAKIPI_RESOURCES_DIR
  	  value: "/tmp"
	- name: JAVA_TOOL_OPTIONS
  	  value: "-agentpath:/takipi/lib/libTakipiAgent.so"
  volumeMounts:
	- mountPath: /takipi
  	  name: takipi-volume
  volumes:
	- name: takipi-volume

Download and unzip the latest Micro-Agent to create a takipi folder on the Persistent Volume.

For Red Hat / Debian based images: https://s3.amazonaws.com/app-takipi-com/deploy/linux/takipi-agent-latest.tar.gz

For Alpine Linux based images (beta): https://s3.amazonaws.com/app-takipi-com/deploy/alpine/takipi-agent-latest.tar.gz

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Note

If you're sharing the same Agent through a mount across multiple containers, set the environment variable TAKIPI_RESOURCES_DIR=/tmp to avoid conflicts and to ensure each Agent writes to its own folder.

Copy

To copy the Micro-Agent into your image, add the following lines to your Dockerfile:

# set default environmental variables
ENV TAKIPI_COLLECTOR_HOST=collector
ENV TAKIPI_COLLECTOR_PORT=6060
ENV JAVA_TOOL_OPTIONS=-agentpath:/takipi/lib/libTakipiAgent.so

# Download and install the agent - extracts into the `takipi` folder.
# NOTE: Use the correct Agent for your OS
RUN curl -sL https://s3.amazonaws.com/app-takipi-com/deploy/linux/takipi-agent-latest.tar.gz | tar -xvzf -

Next Steps

Naming your Application, Server, Deployment

  • Option 1: Using JVM arguments passed at application start-up
  • Option 2: Using JAR or WAR manifest attributes

Updated about 2 years ago