telegraf/docs/specs/tsd-002-custom-builder.md

Telegraf Custom-Builder

Objective

Provide a tool to build a customized, smaller version of Telegraf with only the required plugins included.

Keywords

tool, binary size, customization

Overview

The Telegraf binary continues to grow as new plugins and features are added and dependencies are updated. Users running on resource constrained systems such as embedded-systems or inside containers might suffer from the growth.

This document specifies a tool to build a smaller Telegraf binary tailored to the plugins configured and actually used, removing unnecessary and unused plugins. The implementation should be able to cope with configured parsers and serializers including defaults for those plugin categories. Valid Telegraf configuration files, including directories containing such files, are the input to the customization process.

The customization tool might not be available for older versions of Telegraf. Furthermore, the degree of customization and thus the effective size reduction might vary across versions. The tool must create a single static Telegraf binary. Distribution packages or containers are not targeted.

Prior art

PR #5809 and telegraf-lite-builder:

• Uses docker
• Uses browser:
  • Generates a webpage to pick what options you want. User chooses plugins; does not take a config file
  • Build a binary, then minifies by stripping and compressing that binary
• Does some steps that belong in makefile, not builder
  • Special case for upx
  • Makes gzip, zip, tar.gz
• Uses gopkg.in?
• Can also work from the command line

PR #8519

• User chooses plugins OR provides a config file

powers/telegraf-build

• User chooses plugins OR provides a config file
• Currently kept in separate repo
• Undoes changes to all.go files

rawkode/bring-your-own-telegraf

• Uses docker

Additional information

You might be able to further reduce the binary size of Telegraf by removing debugging information. This is done by adding -w and -s to the linker flags before building LDFLAGS="-w -s".

However, please note that this removes information helpful for debugging issues in Telegraf.

Additionally, you can use a binary packer such as UPX to reduce the required disk space. This compresses the binary and decompresses it again at runtime. However, this does not reduce memory footprint at runtime.