How do I programmatically find out my PermGen space usage?

Question

I'm trying to diagnose a java.lang.OutOfMemoryError: PermGen Space error when running on Sun's Hotspot JVM, and would like to know how much PermGen space my program is using at various points. Is there a way of finding out this information programmatically?

score 38 · Accepted Answer · edited Apr 10 '14 at 10:52

38

You can use something like this:

Iterator<MemoryPoolMXBean> iter = ManagementFactory.getMemoryPoolMXBeans().iterator();
while (iter.hasNext())
{
    MemoryPoolMXBean item = iter.next();
    String name = item.getName();
    MemoryType type = item.getType();
    MemoryUsage usage = item.getUsage();
    MemoryUsage peak = item.getPeakUsage();
    MemoryUsage collections = item.getCollectionUsage();
}

This will give you all types of memory. You are interested in "Perm Gen" type.

edited Apr 10 '14 at 10:52

jleft

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answered Mar 30 '09 at 14:21

kgiannakakis

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Thanks, this works. I am taking the MemoryPoolMXBean where name.equalsIgnoreCase("Perm Gen"). – Simon Nickerson Mar 30 '09 at 15:14
Needed info, Thank you kgiannakakis. – vissu Jul 12 '12 at 06:30

score 3 · Answer 2 · answered Mar 30 '09 at 14:05

3

Try ManagementFactory.getMemoryPoolMXBeans().

answered Mar 30 '09 at 14:05

Joachim Sauer

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Thank you for getting me started. – Simon Nickerson Mar 30 '09 at 15:14

How do I programmatically find out my PermGen space usage?

2 Answers2

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