> 1) does OpenJ9
support JMX for monitoring purposes? I've tried to
enable them the same way as Oracle's one, but it doesn't
listen on a port.
OpenJ9 should support JMX as its
being tested regularly in the builds . Have you
set a port using an option like '-Dcom.sun.management.jmxremote.port=9999'?
If that doesn't solve it, please open an issue on GitHub so we can help dig
into this with you. Test cases, command lines, etc
> 4) is it possible to list the available
flags? Documentation is quite limited, I wasn't able to find
out a comprehensive list with descriptions.
The full set of options haven't been documented
at the OpenJ9 project yet. Most of the documentation for
IBM's JDK still applies
I'll let some of the GC devs respond to
questions around which policy to pick and how to rotate the
Original message -----
From: akrus <akrus@xxxxxxxxxxx>
Sent by: openj9-dev-bounces@xxxxxxxxxxx
Subject: [openj9-dev] OpenJ9 question
Date: Mon, Nov 20, 2017 5:50 AM
Hello everyone! (if somebody is here)
I have several questions related to OpenJ9, but apart
from Github issues and this mailing list I wasn't able to
find another place to ask.
1) does OpenJ9 support JMX for monitoring purposes? I've
tried to enable them the same way as Oracle's one, but it
doesn't listen on a port.
2) with -Xgcpolicy:metronome and heap >25Gb I get this
Selected VM [default] does not exist.
Is it expected behavior? Metronome GC doesn't support
heaps larger than 25Gb?
3) what's the best GC option for low latency apps? Does do
not say this directly, but is it Metronome? Are there any
flags than can further reduce GC pauses? -Xrealtime
doesn't work, is it unavailable completely or it's a part
of some subscription?
4) is it possible to list the available flags?
Documentation is quite limited, I wasn't able to find out
a comprehensive list with descriptions.
5) how to rotate GC logs? are the flags
-XX:GCLogFileSize=100M supported? Does OpenJ9 accept a
signal to flush the logs?
Thanks in advance.
Btw, is there any IRC chat or something similar available
for general questions?