class metadata

[Y Srinivas Ramakrishna]

> Thanks. Running the default collectors so I'm believing that these 
> should be collected. These are from the C++ layer?

Sorry, i was not very clear. No, this is from the JVM's representation of
the classes used by the application that the JVM is running.
It's possible that the classes here are in fact being actively
used by your application and/or represent the classes that were
loaded by the system class-loader and will therefore never be unloaded?
(although the total size occupied by them here appears suspiciously
large.) Check "jmap -permstat" for more information; you might also
want to try a more recent jvm perhaps.

best.
-- ramki


> 
> Regards,
> Kirk
> 
> Y Srinivas Ramakrishna wrote:
> > These are class meta-data that live in the perm gen.
> >
> > -- ramki
> >
> > ----- Original Message -----
> > From: kirk <kirk.pepperdine at gmail.com>
> > Date: Monday, October 13, 2008 8:56 am
> > Subject: Re: CMS collection keep working during holiday
> > Cc: hotspot-gc-dev at openjdk.java.net
> >
> >
> >   
> >> Hi,
> >>
> >> I've got a histogram that includes a number of classes that I've 
> not 
> >> seen at the top of a histogram just yet. This is a pre-gc histogram 
> 
> >> from 
> >> the 1.5.0_15. Any thoughts on what might cause these to build up?
> >>
> >>       1 Object Histogram:
> >>       2
> >>       3 Size    Count   Class description
> >>       4 -------------------------------------------------------
> >>       5 2009570160      35394   int[]
> >>       6 25703600        237926  char[]
> >>       7 23512384        20129   byte[]
> >>       8 18761568        144582  * ConstMethodKlass   <----
> >>       9 10416360        144582  * MethodKlass            <----
> >>      10 8144800 194428  * SymbolKlass                   <----
> >>      11 7925040 13619   * ConstantPoolKlass            <----
> >>      12 6832800 284700  java.lang.String
> >>      13 5619232 13619   * InstanceKlassKlass            <----
> >>      14 4503280 11914   * ConstantPoolCacheKlass    <----
> >>      15 3498664 37130   java.util.HashMap$Entry[]
> >>      16 3116000 97375   java.util.TreeMap$Entry
> >>      17 3067808 37737   java.lang.Object[]
> >>      18 2498800 31235   java.lang.reflect.Method
> >>      19 2364600 98525   java.util.HashMap$Entry
> >>      20 1683520 42088   org.apache.velocity.runtime.parser.Token
> >>      21 1626552 5532    * MethodDataKlass          <----
> >>
> >> Regards,
> >> Kirk Pepperdine
> >>
> >>     
> >
> >   
>