Does .NET have something like Java's permgen?

Question

So I've got a pretty standard spring, hibernate, tomcat environment.. yet I'm getting permgens locally and on CI.

I know there is a TEMPORARY fix (i.e. increasing the memory assigned to permgen) but this still is only temporary. I'd rather not imagine what a production environment looks like given what I'm seeing.

(a bit of a comparison question) In .NET I have not seen anything similar. Does .NET have its version of permgen?

(in case you do not know what permgen is Significance of PermGen Space )

You are running spring, hibernate and Tomcat...with C#? I am confused. — aquinas, Nov 15 '11 at 20:43
It would not be a c# thing it would be a clr thing. c# is just a language — Ben Robinson, Nov 15 '11 at 20:43
You could describe a bit more what the permgen is, and its properties. And not sure how your second paragraph relates to the rest. And what are you interested in? — CodesInChaos, Nov 15 '11 at 21:06
If you don't know what permgen is see this http://stackoverflow.com/questions/2238522/significance-of-permgen-space — user48545, Nov 15 '11 at 21:08

Olivier Jacot-Descombes · Answer 1 · 2011-11-22T21:12:17.700

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There is no such thing in the CLR. Just a ordinary heap. The garbage collector (GC) is generational, with three generations. One for young objects, one for long living and one for very long living objects. There is also a lage object heap (LOH). The GC treats the LOH a bit differently in order to increase efficiency. See Large Object Heap Uncovered

edited Nov 22 '11 at 21:12

answered Nov 15 '11 at 21:16

Olivier Jacot-Descombes

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What about for interned strings? Are those not effectively "permgen"? – user2864740 Feb 23 '17 at 05:44
Interning is done for string literals (i.e. strings visible as plain text in the source code), but not for strings created dynamically at runtime. You cannot use it as a general memory management system. – Olivier Jacot-Descombes Feb 23 '17 at 15:10

jeha · Accepted Answer · 2011-11-15T21:15:28.393

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No, the CLR (C# is "just" a CLR language) does not have a permanent generation, see Fundamentals of Garbage Collection.

Btw, future versions of the JVM - currently expected at the latest for Java 8 - won't have permgen either (see Oracle discusses Java 7 & 8 new features on video) (basically as a result of "merging" the "classic" Sun HotSpot VM that has permgen and JRockit JVM).

edited Nov 15 '11 at 21:15

answered Nov 15 '11 at 21:09

jeha

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Does .NET have something like Java's permgen?

2 Answers2