I'm curious -- which other VMs have you used successfully? I've wondered about OpenJDK myself...
At any rate,I think it makes sense to at least document the specific settings of the currently-required VM. I'm game for having a list of VMs instead of a single required VM at some point (provided they're Java 6+). But I think if we're going to recommend any other VMs, we really should be testing with them as part of the dev/release cycle. - Chris On Mon, Jul 25, 2011 at 4:01 PM, <aj...@virginia.edu> wrote: > I recognize the requirement, but I happily run Fedora over other > HotSpot-variants in development. My point is only that we would ideally _not_ > require a particular VM, although I also recognize that we require a certain > level of predictability for good support. > > Those options are exactly the ones to which I was referring. They work > perfectly well in our experience, but we have _not_ done real, formal > testing. This might be very worthwhile. > > --- > A. Soroka > Online Library Environment > the University of Virginia Library > > > > > On Jul 25, 2011, at 3:52 PM, Chris Wilper wrote: > >> Currently we do require the Sun/Oracle version of Java 6, so the >> settings should be consistent across VMs. >> >> Incidently, are you familiar with CMSClassUnloadingEnabled and >> UseConcMarkSweepGC? Apparently both are required to get the Sun/Oracle >> VM to attempt to unload old classes. >> >> But I'm hesitant to recommend much without the actual tuning experience. >> >> - Chris >> >> On Mon, Jul 25, 2011 at 11:30 AM, <aj...@virginia.edu> wrote: >>> This is even more relevant for those sites which are running a repository >>> in the same container as other applications (which may be hungry for >>> PermGen themselves). >>> >>> I've never seen the behavior that a repository starts up fine but >>> eventually runs out of PermGen, which suggests against a memory leak, to >>> me. I have many times seen a repository in a container with other apps fail >>> to get up and running very quickly after JVM startup with PermGen >>> problems. My experience has been that Fedora simply had a large appetite >>> for classes and that appetite is fairly constant. >>> >>> We might also consider offering advice (but this would get pretty >>> JVM-specific) about setting class unloading behavior. >>> >>> --- >>> A. Soroka >>> Online Library Environment >>> the University of Virginia Library >>> >>> >>> >>> >>> On Jul 25, 2011, at 8:35 AM, Chris Wilper wrote: >>> >>>> While running ConfigB tests on 3.5-SNAPSHOT with Oracle on Windows 7 >>>> x64 last week, the embedded Tomcat gave me the dreaded >>>> "OutOfMemoryError: PermGen Space". Has anyone else seen this yet when >>>> running 3.5-SNAPSHOT? (particularly on 64-bit Windows or Linux) >>>> >>>> After looking into the problem a bit, I am coming around to the >>>> conclusion that we should be recommending people set a maximum permgen >>>> size to the VM (e.g. -XX:MaxPermSize=256m). >>>> >>>> Here's what I did after noticing the error: >>>> >>>> 1) Stopped tomcat and added the following line to >>>> %FEDORA_HOME%\tomcat\bin\setclasspath.bat >>>> >>>> set JAVA_OPTS=-Dcom.sun.management.jmxremote.port=8086 >>>> -Dcom.sun.management.jmxremote.ssl=false >>>> -Dcom.sun.management.jmxremote.authenticate=false -XX:MaxPermSize=256m >>>> >>>> 2) Started Tomcat and fired up VisualVM, adding the JMX Connection to port >>>> 8086 >>>> >>>> 3) Ran mvn install -Dconfig=B and watched what it said about PermGen size. >>>> >>>> Here's what I noticed: >>>> >>>> Prior to the tests starting, PermGen was at about 54m with about 7200 >>>> classes loaded. >>>> After the tests ran for a few minutes, PermGen grew and seemed to >>>> level out at about 98m with about 13500 classes loaded. >>>> >>>> It's quite possible we have a classloader leak somewhere. But even if >>>> we don't, it seems we should be recommending a bigger MaxPermSize than >>>> the default, 64m. >>>> >>>> - Chris >>>> >>>> ------------------------------------------------------------------------------ >>>> Storage Efficiency Calculator >>>> This modeling tool is based on patent-pending intellectual property that >>>> has been used successfully in hundreds of IBM storage optimization engage- >>>> ments, worldwide. Store less, Store more with what you own, Move data to >>>> the right place. Try It Now! >>>> http://www.accelacomm.com/jaw/sfnl/114/51427378/ >>>> _______________________________________________ >>>> Fedora-commons-developers mailing list >>>> Fedora-commons-developers@lists.sourceforge.net >>>> https://lists.sourceforge.net/lists/listinfo/fedora-commons-developers >>> >>> >>> ------------------------------------------------------------------------------ >>> Storage Efficiency Calculator >>> This modeling tool is based on patent-pending intellectual property that >>> has been used successfully in hundreds of IBM storage optimization engage- >>> ments, worldwide. Store less, Store more with what you own, Move data to >>> the right place. Try It Now! >>> http://www.accelacomm.com/jaw/sfnl/114/51427378/ >>> _______________________________________________ >>> Fedora-commons-developers mailing list >>> Fedora-commons-developers@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/fedora-commons-developers >>> >> >> ------------------------------------------------------------------------------ >> Storage Efficiency Calculator >> This modeling tool is based on patent-pending intellectual property that >> has been used successfully in hundreds of IBM storage optimization engage- >> ments, worldwide. Store less, Store more with what you own, Move data to >> the right place. Try It Now! http://www.accelacomm.com/jaw/sfnl/114/51427378/ >> _______________________________________________ >> Fedora-commons-developers mailing list >> Fedora-commons-developers@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/fedora-commons-developers > > > ------------------------------------------------------------------------------ > Storage Efficiency Calculator > This modeling tool is based on patent-pending intellectual property that > has been used successfully in hundreds of IBM storage optimization engage- > ments, worldwide. Store less, Store more with what you own, Move data to > the right place. Try It Now! http://www.accelacomm.com/jaw/sfnl/114/51427378/ > _______________________________________________ > Fedora-commons-developers mailing list > Fedora-commons-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/fedora-commons-developers > ------------------------------------------------------------------------------ Storage Efficiency Calculator This modeling tool is based on patent-pending intellectual property that has been used successfully in hundreds of IBM storage optimization engage- ments, worldwide. Store less, Store more with what you own, Move data to the right place. Try It Now! http://www.accelacomm.com/jaw/sfnl/114/51427378/ _______________________________________________ Fedora-commons-developers mailing list Fedora-commons-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/fedora-commons-developers
