isabella232 / jruby-startup

A collection of utilities to help improve JRuby startup time

JRuby::Startup

This is a collection of utilities to help improve the startup time of JRuby-based applications.

Installation

gem install jruby-startup

Usage

The utilities provided by this gem are described below.

generate-appcds

The generate-appcds command is used to generate an AppCDS, or "Application-specific Class Data Store" archive on OpenJDK 11 or higher. This archive pre-processes the classes in JRuby to eliminate some overhead at startup.

By using this utility and setting some environment variables, many JRuby commands can be sped up a fair amount.

Running generate-appcds alone will generate the AppCDS archive based on a command line of -e 1 as passed to JRuby. You can provide a different command line, in quotes, to the generate-appcds command.

$ generate-appcds
*** Outputting list of classes at /Users/headius/projects/jruby/lib/jruby.list
...

When the command has completed, you will see some environment variables to set that will enable the use of the AppCDS archive.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/jruby/jruby-startup.