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When a flight recording is started from the Java Mission Control Client, it records the status of the JVM process during the specified time period. The Flight Recorder then creates a file containing the recorded data. The recording file is automatically opened in the Java Flight Recorder tool upon completion of the recording.
The Java Flight Recorder (JFR) is a performance monitoring and profiling tool that makes diagnostics information always available, even in the wake of catastrophic failure, such as a system crash. At its most basic, JFR is a rotating buffer of diagnostics and profiling data that is always available, on demand. You might consider it a sort “time machine” that enables you to go back in time to gather diagnostics data leading up to an event. The data stored in the rotating buffer includes JVM and application events.
In Java Mission Control Client, the Flight Recorder allows users who are running a Flight Recorder-compliant version of the JVM (that is, JDK 7 Update 4 or later) to view the JVM's recordings, current recording settings, and runtime parameters on a series of tabs that aggregate performance data into logical, task-based groups. The data on these tabs is presented by way of an assortment of dials, chart, and tables. At the top of each tab is a sliding window, called the Range Navigator, with which you can expand or narrow the range of reporting; for example, if you see a group of events clustered around a specific time period, you can adjust the Range Navigator to include just those events, with the resulting data for just those events appearing on the tab components.