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Figure 3-9. Java Flight Recorder general information
This display is quite similar to what Java Mission Control displays when doing basic monit-
oring. Above the gauges showing CPU and heap usage, there is a timeline of events (repres-
ented by a series of vertical bars). The timeline allows us to zoom into a particular region of
interest; although in this example the recording was taken over a 6-minute period, I zoomed
into a 1:06 interval near the end of the recording.
The graph here for CPU usage is a little clearer as to what is going on; the GlassFish JVM is
the bottom portion of the graph (averaging about 70% usage), and the machine is running at
100% CPU usage. Along the bottom, there are some other tabs to explore: information about
system properties and how the JFR recording was actually made. The icons that run down
the lefthand side of the window are more interesting: those icons provide visibility into the
application behavior.
JFR Memory view
The information gathered here is extensive. Figure 3-10 shows just one panel of the Memory
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