tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jeffrey Janner" <>
Subject RE: [OT] Jconsole Perform GC?
Date Tue, 09 Nov 2010 15:51:08 GMT
Thanks Chuck.  Just what I was interested in.

> -----Original Message-----
> From: Caldarale, Charles R []
> Sent: Tuesday, November 09, 2010 9:05 AM
> To: Tomcat Users List
> Subject: RE: [OT] Jconsole Perform GC?
> > From: Jeffrey Janner []
> > Subject: [OT] Jconsole Perform GC?
> > Anyone know what exactly what kind of GC the "Perform GC"
> > button in Jconsole does?
> The same one you get by calling System.gc() - a full GC.
> > The initial work was mostly in the Eden space and Survivor
> > spaces for most of the day, then suddenly, a big chunk
> > (nearly 4GB) ended up in the Old Gen space and pretty much
> > stayed there all night.
> Anything too big for the Eden space will be allocated directly in
> tenured.
> > Looking at the other individual graphs showed that there had
> > been several instances of GC performed by the JVM during that
> > time, but it took my manual instance to clear the Old Gen.
> Those were minor collections, cleaning out only the Eden space.
> > Is this just "normal" JVM GC processing?
> Yes, that's completely normal.  The JVM will not do a major (full) GC
> unless it has to - or is forced by the API invocation.
>  - Chuck
> PROPRIETARY MATERIAL and is thus for use only by the intended
> recipient. If you received this in error, please contact the sender
> delete the e-mail and its attachments from all computers.
> ---------------------------------------------------------------------
> To unsubscribe, e-mail:
> For additional commands, e-mail:


Confidentiality Notice:  This Transmission (including any attachments) may contain information
that is privileged, confidential, and exempt from disclosure under applicable law.  If the
reader of this message is not the intended recipient you are hereby notified that any dissemination,
distribution, or copying of this communication is strictly prohibited.  

If you have received this transmission in error, please immediately reply to the sender or
telephone (512) 343-9100 and delete this transmission from your system.

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message