logging-log4j-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Gary Gregory <garydgreg...@gmail.com>
Subject Re: still: Memoryleak - org.apache.log4j.helpers.ThreadLocalMap
Date Thu, 17 Dec 2015 23:32:47 GMT
Can you list which bugs in JIRA you'd like to have in what could possibly
be a 2.3.1 release?

Gary

On Thu, Dec 17, 2015 at 2:57 PM, Dave Glasser <dglasser@pobox.com> wrote:

> Unfortunately, in addition to the bugs in 2.3, there is missing
> functionality that precluded me from using it. (The programmatic
> configuration features I posted about in the last week or so.)
> If there isn't currently any actively maintained branch that supports 1.6,
> I'll have to work around it some other way.
>
>
>
>       From: Gary Gregory <garydgregory@gmail.com>
>  To: Dave Glasser <dglasser@pobox.com>; Log4J Users List <
> log4j-user@logging.apache.org>
>  Sent: Thursday, December 17, 2015 3:16 PM
>  Subject: Re: still: Memoryleak - org.apache.log4j.helpers.ThreadLocalMap
>
> Hello,
>
> Log4j 1 has reached EOL. For Java 6 support you can use 2.3.
>
> Gary
> On Dec 17, 2015 11:30 AM, "Dave Glasser" <dglasser@pobox.com> wrote:
>
> > To any Log4j devs on the list, if Veit has found a bug in 1.2.17, please,
> > please, fix it and release 1.2.18. I cannot use 2.5 because my code has
> to
> > run under Java 1.6. I suspect that is the case with a lot of developers
> who
> > deploy on WebSphere or WebLogic.
> >
> >
> >
> >      From: Veit Guna <Veit.Guna@gmx.de>
> >  To: log4j-user@logging.apache.org
> >  Sent: Thursday, December 17, 2015 12:36 PM
> >  Subject: still: Memoryleak - org.apache.log4j.helpers.ThreadLocalMap
> >
> > Hi.
> >
> > We're developing a Jersey 2(.22.1) REST service with JDK8, log4j 1.2.16
> > and SLF4J 1.7.7 using Tomcat 8.0.23.
> >
> > Recently I stumbled across the problem mentioned here:
> >
> > https://bz.apache.org/bugzilla/show_bug.cgi?id=50486
> >
> > Where Tomcat complains about left behind ThreadLocalMaps.
> >
> > I updated to 1.2.17 which claims to fix the mentioned problem.
> > On first sight, it did. Starting the server and immediately stopping it
> > showed no warning anymore - before it did. Yay!
> >
> > But then I drove some loadtests against our REST service and after
> > stopping it the same message appeared again :(.
> >
> > I double checked that our MDC put/remove is performed within a
> > try/finally within a http filter. I also logged, what values
> > were put and removed from the MDC - everyting as expected.
> > I also made sure, that the key was really removed after
> > MDC.remove() by getting the key from the MDC again: null.
> >
> > Tomcat complained about a specific key/value in the ThreadLocalMap.
> > I checked, that this key/value was logged before - and it was
> > logged as "removed". So somehow it wasn't _really_ removed.
> >
> > I digged deeper into the rabbit hole and found this peace of code:
> >
> > --cut here--
> > final public class ThreadLocalMap extends InheritableThreadLocal {
> >
> >  public
> >  final
> >  Object childValue(Object parentValue) {
> >    Hashtable ht = (Hashtable) parentValue;
> >    if(ht != null) {
> >      return ht.clone();
> >    } else {
> >      return null;
> >    }
> >  }
> > }
> > --cut here--
> >
> > At this point, the hashtable containing the key/values is cloned
> > when a child thread is spawned. That would explain, why I see that
> > the complained key/value still exists, although I removed it from the
> > MDC. It still exists in the cloned instance on the spawned child thread
> > I guess!
> >
> > I verified it by debugging within eclipse and set a breakpoint there,
> > simply returning null instead of ht.clone(). And voila: no complaining
> > anymore when shutting down.
> >
> > Since I'm not too deep into log4j, could someone of the devs please
> > shed some light on this, please?
> >
> > I'm wondering, who will remove the ThreadLocalMap on the spawned child
> > threads? Since MDC.remove() will do this only on my parent thread
> > manually kicked by the filter.
> >
> > Or, maybe I'm completely wrong with this :).
> >
> > Thanks
> > Veit
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: log4j-user-unsubscribe@logging.apache.org
> > For additional commands, e-mail: log4j-user-help@logging.apache.org
> >
> >
> >
>
>
>




-- 
E-Mail: garydgregory@gmail.com | ggregory@apache.org
Java Persistence with Hibernate, Second Edition
<http://www.manning.com/bauer3/>
JUnit in Action, Second Edition <http://www.manning.com/tahchiev/>
Spring Batch in Action <http://www.manning.com/templier/>
Blog: http://garygregory.wordpress.com
Home: http://garygregory.com/
Tweet! http://twitter.com/GaryGregory

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message