Monitoring plugin memory usage, slow - but workable.

I've been trying to work out how to calculate the total memory usage for each loaded plugin. Turns out that while a mild pain in the ass, it's entirely doable. Here's some output:

Code:

2011-04-22 23:20:08 [INFO] Server : 53171 Kb
2011-04-22 23:20:04 [INFO] Plugin Memory Usage:
2011-04-22 23:20:04 [INFO] 6 plugins
2011-04-22 23:20:11 [INFO] Essentials : 8 Kb
2011-04-22 23:20:15 [INFO] Permissions : 8 Kb
2011-04-22 23:20:15 [INFO] GroupManager : 9 Kb
2011-04-22 23:20:15 [INFO] EssentialsProtect : 314 Kb
2011-04-22 23:20:15 [INFO] EssentialsSpawn : 304 Kb
2011-04-22 23:20:15 [INFO] BukkitCompat : 1 Kb

It's done by using a java agent (Requires a extra command line argument and a class) that implements the java Instrumentation interface to get access to the getObjectSize(<object>) method. Internally it uses this recursively to get the total size for an object.

Be aware that this is very slow. The above output took around 7 seconds to be generated and stalls the server whilst its running - but that said it's still useful for diagnostics.

Eventually this is going to be shipping as part of the McMyAdmin compatibility plugin to let you see plugin memory usage via the web interface (it will only poll when the user asks to view the data)

For more information, see http://sourceforge.net/projects/sizeof/

 

great!

 

I realize this might be a bit much, but could it be possible for you to could give us a quick tutorial on how to use this?

 

I can't wait to see this in action!

 

@PhonicUK

sorry but how i can use this for my server?

 

You can't yet, I've not finished it. It'll be shipping with McMyAdmin once it's ready.

 

@PhonicUK
is this still active?

 

For example:

Code:

java -Xmx320M -Xincgc -javaagent:SizeOf.jar -jar craftbukkit-0.0.1-SNAPSHOT.jar

 

Wonderful idea.

 

Is this done yet? or is there any way to use it? would need it now since my server is taking alot of memory... need to know what plugin

 

This might help, at least somewhat.