default -Xmx8G in wrapper-properties.conf has no effect on agent.jar

Bug Report / Documentation Report

Summary

After encountering for a few times this error:

2020-01-24 14:48:38,619 ERROR [scheduler-2] TaskUtils$LoggingErrorHandler:95 - Unexpected error occurred in scheduled task.
java.lang.OutOfMemoryError: Java heap space

I decided to increase memory for the go-agent. According to this comment and performance tuning docs wrapper-properties.conf is the right place. So I removed # from wrapper.java.additional.105=-Xmx8G in /usr/share/go-agent/wrapper-config/wrapper-properties.conf

It turned out it has no effect.

After some digging I added -Xms1g -Xmx2g to set.default.AGENT_STARTUP_ARGS parameter in wrapper.conf (instead wrapper-properties.conf) and that fixed the java.lang.OutOfMemoryError problem. I’ve noticed that:

1. wrapper.java.additional.* in wrapper-properties.conf works only for agent-bootstrapper.jar
2. AGENT_STARTUP_ARGS in wrapper.conf works for agent.jar, besides Xmx it was also tested with -Dtoggle.agent.git.clean.keep.ignored.files

Environment

Basic environment details

• Go Version: go-agent 19.7.0-9567
• JAVA Version: OpenJDK 64-Bit Server VM AdoptOpenJDK (build 12.0.1+12, mixed mode, sharing)
• OS: Ubuntu 16.04 xenial

Additional Environment Details

Agent installation was upgraded from /etc/default/go-agent

Possible Fix

I’m not familiar with java service wrapper but this line is commented out https://github.com/gocd/gocd/blob/master/installers/include/additional-properties.conf#L3

[arvindsv]

@suside That change you proposed makes sense to me.

You see Xmx in the docs and in the file, which is present on the agent… well it was confusing.

Yes, I understand. If someone gets confused, I think it’s on the documentation to be less confusing and not on the person to have “known better”. So, it’s definitely not on you. 😃

[suside]

I made some changes to make it more clear in #7736, and I’ll update the docs a bit to fix the obvious errors at least. But feel free to make further edits.

👍 What you think about splitting performance_tuning.md Things to Remember into two sections like so https://github.com/suside/docs.go.cd/commit/b0911c08098ff56bc3a67d9538f4d43be11ea44e

I checked and it is clear from the docs that it is talking about the GoCD server and not the agent, but I’ll make a small improvement there.

Yeah, it kinda is now for me too, but when searching for mem error for the first time… You see Xmx in the docs and in the file, which is present on the agent… well it was confusing.