Netbeans上的PermGen空间错误

Question

im getting java.lang.OutOfMemoryError: PermGen space error. I tried to change in netbeans.conf but no success..

i changed

netbeans_default_options="-J-client -J-Xss2m -J-Xms32m -J-XX:PermSize=32m -J-Dapple.laf.useScreenMenuBar=true -J-Dapple.awt.g raphics.UseQuartz=true -J-Dsun.java2d.noddraw=true -J-Dsun.java2d.dpiaware=true -J-Dsun.zip.disableMemoryMapping=true"

to

netbeans_default_options="-J-client -J-Xmx3g -J-Xss2m -J-Xms32m -J-XX:PermSize=512m -J-Dapple.laf.useScreenMenuBar=true -J-Dapple.awt.graphics.UseQuartz=true -J-Dsun.java2d.noddraw=true -J-Dsun.java2d.dpiaware=true -J-Dsun.zip.disableMemoryMapping=true"

it doesnt work.Any tipps ?

Answer 1

For PermGen problems increasing Xmx won't help due to how the memory is partitioned.

But, if you use VisualVM it can help you to visualize how your memory is being used, and you can start to make adjustments.

For one application my PermGen ended up being about 750M in size, but that was for a very large web application.

Hopefully you are using the 64-bit version of Java otherwise you have fewer options.

You can set your max memory size to be 4G, if you have a great deal of memory, and PermGen to perhaps 1G, and then use VisualVM to see how large your memory gets.

If you feel it is too large then you will need to start looking at what is loaded and make decisions, but it helps to see what is happening and work your way down to a more reasonable number.

Answer 2

You are trying to start Netbeans with 32MB (Xms32m). It should be at least 256m (512m for Windows).

If you're still getting that error, you could consider increase Xmx if you have more that 4GB of RAM. On Windows you should leave at least 1.5GB of RAM for the OS