The Java Virtual Machine (JVM) monitoring feature allows you to monitor critical JVM metrics. The critical metrics include heap metrics, non-heap metrics, direct buffer metrics, memory-mapped buffer metrics, garbage collection (GC) details, and JVM thread count. This topic describes the JVM monitoring feature and how to monitor JVM metrics.

Features

The JVM monitoring feature allows you to monitor the following metrics:

  • Instantaneous and accumulated GC details
    • Total times of GC
    • Times of young GC
    • Total time consumption of GC
    • Time consumption of young GC
  • Heap memory details
    • Total heap memory
    • Bytes of old heap memory
    • Bytes of young heap memory (Survivor)
    • Bytes of young heap memory (Eden)
  • Non-heap memory
    • Submitted bytes of the non-heap memory
    • Initial bytes of the non-heap memory
    • Maximum bytes of the non-heap memory
  • Metaspace

    Bytes of metaspace

  • Direct buffer
    • Total bytes of direct buffer
    • Used bytes of direct buffer
  • Number of JVM threads
    • Total number of threads
    • Number of deadlocked threads
    • Number of new threads
    • Number of blocked threads
    • Number of runnable threads
    • Number of terminated threads
    • Number of threads in timed waiting
    • Number of waiting threads

View JVM metrics

  1. On the Applications page, click the application that you want to view.
  2. In the left-side navigation pane, click Application Details.
  3. On the Application Details page, select the node and click JVM monitoring tab on the right side of the page.
    On the JVM monitoring tab, the time sequence curves of the instantaneous GC count, instantaneous GC duration, heap memory details, metadata details, non-heap memory details, direct buffer, and JVM threads are displayed.
    • Click Instantaneous and Accumulated in the upper-right corner of Instantaneous Count / 1 Min and Instantaneous Duration / 1 Min panels. You can view the time sequence curves of the instantaneous GC count or accumulated GC count. You can also view the time sequence curves of instantaneous GC duration.
    • Click a metric name (for example, the total times of GC) on a monitoring panel to enable or disable the visibility of the metric in the chart.
      Note Each chart must contain at least one visible metric. If only one metric is displayed in the chart, you cannot disable the visibility of the metric.
    • Click View API in the upper-right corner of Heap Memory Details / 1 Min, Metadata Details / 1 Min, Non-Heap Memory / 1 Min, Direct Buffer / 1 Min, and JVM Threads / 1 Min panels to view the API details of the monitoring metric.