Question on Shenandoah GarbageCollectorMXBeans

[zgu at redhat.com]

On Fri, 2019-03-01 at 17:26 +0100, Michael Nitschinger wrote:
> No problem at all, thanks for fixing!
I fixed in JDK13, should trickle down to JDK8 through backports.

Thanks,

-Zhengyu

> 
> > On 01.03.2019, at 17:25, zgu at redhat.com wrote:
> > 
> > Hi Michael,
> > 
> > I have no idea how this message went under our radar for so long, I
> > just found out this morning, sorry! 
> > 
> > I filed https://bugs.openjdk.java.net/browse/JDK-8219976, and am
> > working on the fix.
> > 
> > Thanks,
> > 
> > -Zhengyu
> > 
> > On Thu, 2018-11-08 at 10:54 +0100, Michael Nitschinger wrote:
> > > Hi,
> > > 
> > > I’ve been trying to get GC information through the
> > > GarbageCollectorMXBean instances and it is working great so far,
> > > although I have a couple of questions. I couldn’t find any
> > > documentation on this topic, so sorry if it is written up
> > > somewhere.
> > > 
> > > I’m adding my NotificationListener to the MXBeans returned by the
> > > ManagementFactory with shenandoah enabled and:
> > > 
> > > when I’m looking at the “cause” of the
> > > GarbageCollectionNotificationInfo it always says “No GC” which
> > > seems
> > > weird to me (both for the Pauses and the Cycles bean) - even that
> > > the
> > > action contains messages like “end of major GC” or “end of minor
> > > GC".
> > > In terms of “action”, Shenandoah Pauses always seems to return
> > > “end
> > > of major GC” while Shenandoah Cycles returns “end of minor GC”,
> > > but
> > > is that really accurate? There seems to be only one “shenandoah”
> > > memory pool and while the Cycles info has memory usage attached
> > > to
> > > it, the Pauses one has no memory information whatsoever (all
> > > values
> > > are zeroed out).
> > > 
> > > I’m running on 1.8.0_181-b15 that ships with fedora and the only
> > > JVM
> > > flag that I set was -XX:+UseShenandoahGC.
> > > 
> > > Happy to provide more information if required,
> > > Thanks,
> > > Michael 
> > > 
> 
>