Nope. If you _didn't_ null out the reference, you're guaranteed that it
_won't_ get garbage-collected; but if you _do_ null it out, you're only
making it _available_ for garbage collection.
The actual garbage collection only happens when the VM runs out of memory,
or some unspecified time after calling System.gc(). Or, when the VM just
plain wants to--the JLS isn't specific about this.
-- Bill K.
> -----Original Message-----
> From: Jurrius, Mark [mailto:[EMAIL PROTECTED]]
> Sent: Thursday, May 03, 2001 7:43 AM
> To: [EMAIL PROTECTED]
> Subject: RE: Memory usage
>
>
> Correct me if I'm wrong. If for instance I want a bean
> removed knowing that
> System.gc() does not happen immediately, would setting the
> bean equal to
> null force the bean to be removed from memory right away and
> not have to
> rely on the garbage collection to eventually take place?
>
> Mark
>
>
> -----Original Message-----
> From: William Kaufman [mailto:[EMAIL PROTECTED]]
> Sent: Thursday, May 03, 2001 10:07 AM
> To: '[EMAIL PROTECTED]'
> Subject: RE: Memory usage
>
> > That your finalize method is called, doesn't mean that
> > the garbage collector has released your objects. The
> > only way to be shure that this happens, is to explicitly
> > run System.gc().
>
> Even that's not sufficient: it just suggests to the VM that
> garbage-collecting might be a good idea right now. Any actual garbage
> collection would take place later, in another thread.
>
> And, even when it does happen, that doesn't mean all the memory will
> necessarily be released to the OS: the VM will hold on to
> some so that it
> won't need to go back to the OS on the next allocation.
>
> You might want to get a memory profiler (like JProbe) and see
> where the
> memory is going. At the very least, try doing something like,
>
> Runtime rt = Runtime.getRuntime();
> System.err.println("Free="+rt.freeMemory()+",
> total="+rt.totalMemory());
>
> often, to see how much memory is actually in use, and how much is just
> allocated from the OS.
>
> -- Bill K.
>
>
> > -----Original Message-----
> > From: Ralph Einfeldt [mailto:[EMAIL PROTECTED]]
> > Sent: Thursday, May 03, 2001 5:51 AM
> > To: '[EMAIL PROTECTED]'
> > Subject: AW: Memory usage
> >
> >
> > That your finalize method is called, doesn't mean that
> > the garbage collector has released your objects. The
> > only way to be shure that this happens, is to explicitly
> > run System.gc(). Otherwise it's up to the VM when it will
> > free the memory. (Sun's JDK per default only releases
> > memory if otherwise an OutOfMemoryError would occur, so
> > unless you reach this border the VM will constanly grow)
> >
> > See also the options for the JVM:
> > -verbose:gc (Any VM)
> > -Xincgc (Sun SDK 1.3.*)
> > -Xms (Sun + IBM)
> > -Xmx (Sun + IBM)
> >
> > -----Ursprüngliche Nachricht-----
> > Von: Garry De Toffoli [mailto:[EMAIL PROTECTED]]
> > Gesendet: Donnerstag, 3. Mai 2001 14:34
> > An: [EMAIL PROTECTED]
> > Betreff: Memory usage
> >
> > <snip/>
> > I have in trouble with the memory usage with Tomcat 3.21,
> WinNt 2000
> > and Jdk 1.3 of Sun. the problem is that any operation does
> > not release
> > the memory occuped; to control the memory usage I use the
> > Task Manager;
> > when Tomcat start, the memory used from the process Java is
> of 9608 K;
> > when I request a Jsp page that has an error, like a variable
> > not declared,
> > the memory used is 11868K; if I wait for 1 ay also, this
> > value does not
> > change, so the memory used is not released,
> >
> > running a correct Jsp page, the memory used increase, and
> this is not
> > released yet;
> > I have written a log on the finalize method of my class,
> and this is
> > called, so the garbage collector release all my object.
> >
> > This behavoir is normal?
> > Probably changing the version of Tomcat this problem may be
> corrected.
> > <snip/>
> >
>
