On top of all that's been said, I'd add this: Yes, it's likely that you simply need to increase the maxpermsize. Sometimes just another 100-300 can be enough to solve the problem.
But you also want to make sure that this is really the *first* error that puts CF into a bad state. It could be that something else precedes it and precipitates it. Look in in the [cf]\runtime\logs\, in its out log for this instance, at the time of your crash, and look back in that log (before the crash) to see if any other errors or unusual messages show up. If you see none for 1-20 minutes before that permgen message, then that alone would seem to be the problem. As to how it could happen, you're on the right track but not quite right in what you've concluded. The saving of class files is not quite connected as you think. That's about compiling, where the permgen is about loading. CF loads classes into the template cache (and thereby the permgen, when they're first requested--and are not in the cache already, or later when it's no longer in the cache for any reason, including a restart. A class can be removed from the template cache also during the life of the server when the template cache becomes full and it needs to make room for a more newly requested one, by removing the least recently used one). And CF will obtain that class (to load when needed) either by compiling it from source on the fly, or by pulling it from that cfclasses directory (if you have enabled that "save class files" option in the Admin). So how does the permgen get stressed? Most often by excessive loading of templates into the template cache. Again, when it gets full, it removes the oldest to make room for new ones. How could it get full? Because the number of templates that need to be loaded (CFM files, CFCs, and indeed a class is created for each METHOD in a CFC) exceeds its size. The default is 1024. That's also not a hard cap. There is a soft cache on top of that. If you look in the cfclasses directory, see how many files are there. You might even sort it by date modified and see how many are recently edited. If that number is at or near 1024, it's likely your app uses lots of files and therefore creates lots of classes, which can then cause this stress. If you increase the size of the template cache, beware that that cache is stored in the heap, so you may need to raise that, too. (Yes, loading things into the template cache then affects both the heap and the permgen, from my observation.) Does that make sense, does that help? You're right, you don't find much out there about it. Hope this is helpful. I may blog it once we have some back and forth. (I've hinted at this info in some entries, but not devoted one to it.) /charlie From: ad...@acfug.org [mailto:ad...@acfug.org] On Behalf Of Cheyenne Throckmorton Sent: Tuesday, December 06, 2011 10:09 PM To: discussion@acfug.org Subject: [ACFUG Discuss] PermGen CF Server Memory Errors One of our CF servers keeps needing to have the CF service rebooted on it in order to work and continue serving our sites 1-2x / week. Fortunately we do have a web service on one of the other box that monitors this machine to let us know when it starts bugging out again. The error I am getting on the server has to do with an out of memory perm gen space issue, something that there is tons of stuff online about but nothing that I've been able to succinctly tell is a good idea to look toward resolving the issue. Here are the errors we get before the service fails. javax.servlet.ServletException: ROOT CAUSE: java.lang.OutOfMemoryError: PermGen space 12/06 16:24:46 Error [jrpp-3954] - PermGen space The specific sequence of files included or processed is: F:\...................\case-studies\ENDO-enduring-hot-seat-discussion\index. cfm'' 12/06 16:24:46 error ROOT CAUSE: java.lang.OutOfMemoryError: PermGen space javax.servlet.ServletException: ROOT CAUSE: java.lang.OutOfMemoryError: PermGen space Server: Windows Server 2008 R2 64bit ColdFusion 9,0,1,274733 Standard Java Version: 1.6.0_24 RAM 8GB JVM Arguments -server -Dsun.io.useCanonCaches=false -XX:MaxPermSize=192m -XX:+UseParallelGC -Xbatch -Dcoldfusion.rootDir={application.home}/../ -Dcoldfusion.libPath={application.home}/../lib Despite my attendance of multiple Charlie lectures and/or because of such attendance I certainly do not consider myself an expert in the memory underpinnings of CF. What I do believe is happening through some research and late night testing is that essentially the server stores information (in think in cfclasses) that is essentially compiled java code. It does this to speed the delivery of data generated by CF in a caching like mechanism. There is a checkmark in the settings that says "Save Class Files" which I suspect would solve the problem if indeed this area is getting overflowed and not properly Garbage Collected (if GC even runs in PermGen). However, unchecking that is not recommended for a production machine, and it would obviously slow down all of the sites. Similarly I've seen posts that say to just increase the MaxPermSize, but I find many posts after those saying that is not solve and just delaying the problem. I'd rather solve the problem. Additionally, when observing the websites when it is acting up we get a lot of totally blank pages along with 200 OK http response codes. I have also gotten partial pages at times, but that all leads me to some sort of partial template loading until the permgen runs out of memory. Finally, I don't know that it is a 100% deal, but we have launched a new application on this server that makes use of the new ORM Hibernate functionality. This happened right around the same time we started observing these issues. This was my first shot at ORM within CF and I know I need to go back and re-look at how I have the lazy-loading set up. I have a feeling that it can definitely be tuned better and that it's possible this type of code may make heavy use of the permgen space with dynamically loading data in the way that it works. This heavy banging in the permgen along with an untuned JVM may be the combo that is causing our problems, or maybe I'm way off. Figured I'd throw it out there to group to see what thoughts and solutions might be out there beyond my teams continued googling of words like "permgen", "coldfusion", "hibernate", "orm" and "arehart" :) - Cheyenne Throckmorton P.S. Looking forward to seeing folks at Whirlyball tomorrow night. -- Cheyenne Throckmorton - Atlanta, GA Blog : www.CheyenneJack.com Twitter : @cheyennejack Founder : www.AtlantaUserGroups.com www.TheTallStreetJournal.com www.MohawksRock.com ------------------------------------------------------------- To unsubscribe from this list, manage your profile @ http://www.acfug.org?fa=login.edituserform For more info, see http://www.acfug.org/mailinglists Archive @ http://www.mail-archive.com/discussion%40acfug.org/ List hosted by http://www.fusionlink.com -------------------------------------------------------------
