Comments on: How much memory does my ColdFusion variable really use? – Part III

By: Joel Spriggs

Joel Spriggs — Fri, 19 Nov 2010 14:00:39 +0000

I spoke to soon, problem is I run CF standalone. So the jar goes to /Applications/Coldfusion9/runtime/lib instead of /Applications/Coldfusion9/lib and the jvm argument to add into jvm.config was -javaagent:{application.home}/lib/CFMemoryAgent.jar

Thanks!

By: Joel Spriggs

Joel Spriggs — Fri, 19 Nov 2010 13:51:47 +0000

Did anyone ever figure out the jvm arguments to correctly initialise the env? I’ve tried the suggestions and keep getting java.lang.IllegalStateException: Instrumentation environment not initialised.

By: kai

kai — Sun, 25 Apr 2010 02:43:32 +0000

Hi Jay, thx for pointing jVisualVM out. There are a few tools around that do stuff like that and also look deeper into things like garbage collection etc.

I agree – those settings are not something you constantly would want to run in production.

By: Jay

Jay — Thu, 22 Apr 2010 22:46:29 +0000

Kai, thank you for replying. it actually works now. I added it again to the args in order to test it before I send you the information here and now it works. perhaps I had a typo yesterday and that’s why it didn’t work.

while I was still trying to get it to work yesterday, I found the jVisualVM monitor that comes with the JDK. you need to start the JVM with the switches below (which might not be a good idea for a production server), but then you can generate thread and heap dumps and look deep into the results to find out memory allocations etc. pretty cool tool. I thought that your readers might find it useful.

Jay

java.args: -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=9500 -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false

then launch jVisualVM from the JDK\bin folder and connect to localhost:9500 (or whatever port you used in the switches)

By: kai

kai — Thu, 22 Apr 2010 08:59:33 +0000

Jay, have you figured out the javaagent issue? Are you on Windows or Linux/Mac – I wonder if it’s an issue how to specify the path in Windows. Anything in logs and can you provide a bit more info on your setup? The suggestions for the Java code changes are good – the solution discussed here is really just a proof of concept at this stage – I’ll work those changes in a further release, thx!

By: Jay

Jay — Wed, 21 Apr 2010 23:15:10 +0000

cleanup suggestion for the CF object: add a static array of strings for the types-to-ignore, then use the Arrays.asList( String[] ).contains( ) ) method to test if the type is in the list. this will allow to easily add more items to the list in the future:

public static String[] ignoreTypes;

static {

ignoreTypes = new String[] {

“coldfusion.runtime.NeoPageContext”,
“coldfusion.runtime.CfJspPage”,
“coldfusion.monitor.memory.MemoryTrackable”,
“coldfusion.monitor.sql.QueryStat”,
“coldfusion.monitor.memory.MemoryTrackerProxy”,
“javax.servlet.ServletContext”
};
}

then in the internalSizeOf() method, replace all the type tests with

!Arrays.asList( ignoreTypes ).contains( field.getType().getName() )

By: Jay

Jay — Wed, 21 Apr 2010 23:03:11 +0000

I keep getting an error: “Instrumentation environment not initialised”

I realize that this is because the -javaagent switch is not configured properly. I have tried to put it in the jvm.config under
java.args=-server -javaagent:[path on my server]/MemoryCounterAgent.jar [more args follow...]
but I keep getting th error.

any ideas?

tia,

Jay

By: kai

kai — Tue, 09 Mar 2010 23:56:27 +0000

@Hendrik Sorry for the broken link, had a typo in the file name. It works now.

By: Hendrik Kramer

Hendrik Kramer — Tue, 09 Mar 2010 22:48:41 +0000

Very interesting article. I’ll try it within the next days on some parts of our codebase. But the link to the zip is not working (yet)? Link returns “not found” here.