Out of Memory Errors in Eclipse

Eclipse

I was getting lots of PermGen OutOfMemoryErrors while trying to develop with Eclipse.

The following eclipse.ini settings worked on my machine:

--launcher.XXMaxPermSize
1500m
-vmargs
-Xms384m
-Xmx512m
-XX:PermSize=256M
-XX:MaxPermSize=768M

-vmargs
-Xms384m
-Xmx512m
-XX:PermSize=256M
-XX:MaxPermSize=819M

-vmargs
-Xms384m
-Xmx512m
-XX:PermSize=900M
-XX:MaxPermSize=900M

(This made Eclipse use 1.5 GB of memory!)

These did not:

--launcher.XXMaxPermSize
1024m
-vmargs
-Xms512m
-Xmx768m
-XX:PermSize=512M
-XX:MaxPermSize=768M

--launcher.XXMaxPermSize
1536m
-vmargs
-Xms512m
-Xmx768m
-XX:PermSize=512M
-XX:MaxPermSize=768M

-vmargs
-Xms384m
-Xmx819m
-XX:PermSize=256M
-XX:MaxPermSize=819M

-vmargs
-Xms384m
-Xmx640m
-XX:PermSize=900M
-XX:MaxPermSize=900M

The arguments "--launcher.XXMaxPermSize" and "-XX:MaxPermSize=" do the same thing, and later values override earlier values.

"-XX:PermSize" and "-XX:MaxPermSize" are two separate pools that combine on top of "-Xms" and "-Xmx", so you can combine them together to use lots of memory.