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Java HotSpot Virtual Machine

Events shown in the Range Navigator when viewing System Properties for a JFR recording

5af06565-fdcb-41d4-9d87-adcbe3f7d91bSep 23 2015 — edited Sep 24 2015

What are the events shown in the Range Navigator when viewing the System Properties tab for a Java Flight Recorder recording? I'm guessing that they mark the times when JFR is writing events to disk.

I'm asking because, when capturing a lot of information using JFR, we see two effects that correlate with these events: (1) CPU use ramps up a bit between one event and the next, dropping back to the starting level after each event, even though the application workload is constant; (2) the clock used for high-resolution timestamping on all the events JFR captures appears  to run slower in the period immediately following each of these events, perhaps for the period while JFR is writing to disk. The slowing of the clock appears as an increase in the rate of events shown in the Range Navigator in other tabs - I've also parsed selected  events out of the original FR file to check their apparent rates.

I'm seeing this on Java EE applications running on JBoss EAP 6.x, on Java 7 on small vSphere virtual machines.

This post has been answered by Klara Ward Java Mission Control Dev-Oracle on Sep 23 2015
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Locked on Oct 22 2015
Added on Sep 23 2015