HeapDumper Pluging

This plugin adds the /heapdump command to your server, it requires the permission heapdump which is given to OP players by default.

The command takes a memory heap dump and saves it as a file in the server's directory. The file name uses the current system time by default, but you can customize it by command argument.

Be aware that the heap dump files are usually very big since it will dump the entire application memory in use in a single file, this means that if your server is using 4GB of RAM when the command is executed, the file will also take 4GB in the disk space.

Also be aware that heap dump files may contains sensitive information, like database connection information and unencrypted passwords, so never leave the dumps there.

Commands and Permissions

Command	Permission	Usage	Description
/heapdump	heapdumper.heapdump	/heapdump <optional-filename>	Take a heap dump to analyze memory leak issues and save in the server's folder
/cleardump	heapdumper.cleardump.single	/cleardump <filename>	Deletes a specific heap dump file
/clearalldumps	heapdumper.cleardump.all	/clearalldumps	Deletes all heap dump files at once

Glob Permissions

• heapdumper.cleardump.* - Allows the user to run the command that clears the dumps
  • heapdumper.cleardump.single
  • heapdumper.cleardump.all
• heapdumper.* - Allows the user to run all the heapdumper commands
  • heapdumper.heapdump
  • heapdumper.cleardump.*

Cloning and importing

1. Just do a normal git clone https://github.com/PowerNukkit/HeapDumper-Plugin.git (or the URL of your own git repository)
2. Import the pom.xml file with your IDE, it should do the rest by itself

Debugging

1. Create a zip file containing only your plugin.yml file
2. Rename the zip file to change the extension to jar
3. Create an empty folder anywhere, that will be your server folder.
   Note: You don't need to place the PowerNukkit jar in the folder, your IDE will load it from the maven classpath.
4. Create a folder named plugins inside your server folder
   Note: It is needed to bootstrap your plugin, your IDE will load your plugin classes from the classpath automatically, so it needs to have only the plugin.yml file.
5. Move the jar file that contains only the plugin.yml to the plugins folder
6. Create a new Application run configuration setting the working directory to the server folder and the main class to: cn.nukkit.Nukkit
   
7. Now you can run in debug mode. If you change the plugin.yml you will need to update the jar file that you've made.