Memory(Heap) is managed in generations, or memory pools holding objects of different ages. Garbage collection occurs in each generation when the generation fills up. Objects are allocated in a generation for younger objects or the young generation, and because of infant mortality most objects die there.
When any new object is constructed it goes to Eden space which is a part of Young Generation. If object is still alive after some time it goes to tenured generation where long lived objects lie. The permanent generation is special because it holds meta-data describing user classes (classes that are not part of the Java language). Examples of such meta-data are objects describing classes and methods and they are stored in the Permanent Generation. Applications with large code-base can quickly fill up this segment of the heap which will cause java.lang.OutOfMemoryError: PermGen this article may help http://www.aliaspooryorik.com/blog/index.cfm/e/posts.details/post/tuning-the-jvm-275 On Tue, Sep 3, 2013 at 6:40 PM, Michael Dinowitz <mdino...@houseoffusion.com > wrote: > > > Also Michael - 2gb perm size seams rather large generally speaking > (unless > > you have tons of cfm/cfc files). Further if your server has 8GB of ram, > and > > you are setting 6GB max heap and 2GB max perm size then you are not > leaving > > any room for the OS to operate when things get full. > > > I thought that the perm size was a subset of the heap. From what you say > above, the perm is in addition to the heap. > > I'm going to run some calculations to get a good idea of what the permsize > should be for the app and readjust. > > > > > The perm size does not usually change much once the application is fully > > loaded and all possible logic routes have executed at least once (unless > > you have some sort of dynamic cfml generating going on) so you should be > > able to see how much you are actually using at runtime by running this > > code: http://www.petefreitag.com/item/821.cfm > > > > -- > > Pete Freitag - Adobe Community Professional > > http://foundeo.com/ - ColdFusion Consulting & Products > > http://hackmycf.com - Is your ColdFusion Server Secure? > > http://www.youtube.com/watch?v=ubESB87vl5U - FuseGuard your CFML in 10 > > minutes > > > > > > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:356702 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
