Eclipse Memory Issues

JDK 5 was the default Java version in use, upgraded to JDK1.6.0_21-b06 today and Eclipse started tanking. Starts up fine but after a few minutes would fail with the error 'Internal plug-in action delegate error on creation. PermGen space'. Right, seemed to indicate that I wasn't allocating enough memory for permgen. But the same program works fine with the very same memory settings under JDK 5, so this was definitely an upgrade problem. So much for my support of auto updates :-|

The default setting in eclipse.ini was
--launcher.XXMaxPermSize
256m
-vmargs
-Dosgi.requiredJavaVersion=1.5
-Xms40m
-Xmx256m

And 256m is generally sufficient for permgen, so what gives. Checked the configuration file to confim if the settings had taken effect (Click on Help -> About Eclipse -> Installation Details -> Configuration). Shows up the Xms and Xmx, but no MaxPermGen, hmmm... interesting.
eclipse.vmargs=-Dosgi.requiredJavaVersion=1.5
-Xms40m
-Xmx256m

Googled a bit. The eclipse wiki indicated that it was a bug with Oracle/Sun JDK 1.6.0_21 (had to be my version, duhhh), being tracked as 319514. The bug link is a pretty interesting read.

Apparently, as part of Oracle's rebranding of Sun's products, the Company Name property of the java.exe file, the executable file containing Oracle's JRE for Windows, was updated from "Sun Microsystems" to "Oracle" in Java SE 6u21. Now on Windows, Sun VM is identified using the GetFileVersionInfo API, which reads the company name (present under version details) from jvm.dll or the java executable and compares it against the string "Sun Microsystems". Post update 21, the company name was "Oracle" and the launcher does not recognize this string, hence the -XX:MaxPermSize setting is not honoured.

The workarounds are
- Switch back to '1.6.0_20'
- Change the commandline for launching or add the following line after "-vmargs" to your Eclipse.ini file:-XX:MaxPermSize=256m
- For 32-bit Helios, download the fixed eclipse_1308.dll and place it into (eclipse_home)/plugins/org.eclipse.equinox.launcher.win32.win32.x86_1.1.0.v20100503
- Download and install any of the upgraded versions i.e. version 1.6.0_21-b07 or higher from the java site (alternative link is http://java.sun.com/javase/downloads/index.jsp). Make sure you have b07 or higher by running java -version.

Went with the last option and so far life's good. The MaxPermSize setting shows up under vm options
eclipse.vmargs=-Dosgi.requiredJavaVersion=1.5
-Xms40m
-Xmx256m
-XX:MaxPermSize=256m

But got this bad feeling that when I move to JDK 7, there'll be a newer set of problems cropping up (From the Oracle site: In consideration to Eclipse and other potentially affected users, Oracle has restored the Windows Company Name property value to "Sun Microsystems" in further JDK 6 updates. This value will be changed back to "Oracle" in JDK 7.) Sigh, so much for compatibility.