If somebody writes a tool that plots the values that the perf counters
provide, which is bound to happen if it is exposed via JMX, but then the
internals of the JVM is changed and the perf counter value is removed or
it is incorrect.
Erik
Hi Erik,
I am not sure if Perf Counters could be disabled. If yes, then
PerfCounter MBean must throw appropriate exception while getting
MBeanInfo.
I don't know about tests for PerfCounter. The webrev contains tests
for PerfCounter MBean.
I am not sure how we will be breaking other's code. Could you please
elaborate?
Thanks
Harsha
On Monday 27 February 2017 07:39 PM, Erik Gahlin wrote:
Hi Harsha,
How will perf counters be supported?
Can they be removed at anytime, or only at major releases etc. Do we
have tests for them? I think it would be good know, and perhaps state
somewhere so we don't break people's code.
Erik
Hi All,
Please review the below RFE,
JDK-8007141 <http://JDK-8007141> : Introduce Dynamic MBean exposing
the perf counters.
with webrev at,
http://cr.openjdk.java.net/~hb/8007141/webrev.00/
Appreciate if I can get inputs for below.
1. Location of HotSpotPerfCounterMBean. It is located at
src/jdk.management/share/classes/com/sun/management/internal. It can
be moved to src/jdk.management/share/classes/com/sun/management if
required.
2. Javadoc comments for HotSpotPerfCounterMBean. Not sure if it is
adequate.
3. Description for each attribute of MBean. I am using getUnits(),
getVariability(), and getFlags() for description. I am not sure if
that is the right description. Appreciate inputs from someone who
knows perf counters well.
Thanks
Harsha
