JVM¶
This function monitors JVMInfo, JVMMonitor, GC, thread, and JavaMethod.
Going to the JVM Page¶
Log in to the management console.
Click
on the left and choose Management & Deployment > Application Performance Management.In the navigation pane, choose Application Monitoring > Metrics.
In the tree on the left, click
next to the target environment.Click the JVM tab. By default, the JVMMonitor information of all instances is displayed.
Figure 1 Going to the JVM page¶
On the displayed JVM tab page, select a target instance and monitoring item to view the monitoring data in different metric sets.
Figure 2 Selecting an instance and monitoring item¶
Select a time range. Default: Last 20 minutes.
Options: Last 20 minutes, Last hour, Last 3 hours, Last 6 hours, Last day, Today, Yesterday, Last week, Last month, or Custom.
Figure 3 Selecting a time range¶
Viewing JVM Information¶
On the JVM tab page, view the JVMInfo metrics of the corresponding instance. For details about the metrics, see Table 1.
Figure 4 Viewing JVM information¶
Metric Set | Metric | Description |
|---|---|---|
JVMInfo | JavaAgent Version | Java Agent version |
Started | JVM startup time | |
Startup Parameter | JVM startup parameter | |
Java Class Library Path | Java class library path | |
Java Version | Java version | |
Java Specification Version | Java specification version | |
OS | OS name | |
OS Version | OS version | |
arch | CPU architecture | |
Processors | Number of processors | |
SDK Version | SDK version |
Viewing JVM Monitoring Data¶
APM monitors JVM metrics. For details about the metrics, see Table 2. JVM monitoring metrics are displayed in graphs, so that you can view and analyze JVM monitoring data more easily.
Figure 5 Viewing JVM monitoring data¶
Metric Set | Metric | Description |
|---|---|---|
Thread | Current Threads | Number of current threads |
Deadlock Threads | Number of deadlock threads | |
Daemon Threads | Number of daemon threads | |
Started Threads | Number of started threads | |
Peak Threads | Peak number of threads | |
Thread Status | Waiting Threads | Number of waiting threads |
Terminated Threads | Number of threads in the terminated state | |
Runnable Threads | Number of runnable threads | |
Blocked Threads | Number of blocked threads | |
New Threads | Number of new threads | |
Timed Waiting Threads | Number of threads that timed out | |
Memory | Used Non-Heap Memory | Size of the used non-heap memory |
Used Heap Memory | Size of the used heap memory | |
Used Direct Memory | Size of the used direct memory | |
Class loading | Current Classes | Number of current classes |
Total Loaded Classes | Total number of loaded classes | |
Unloaded Classes | Number of unloaded classes | |
Memory pool | committed(M) | Size of available memory |
init(M) | Size of the initialized memory | |
max(M) | Size of the maximum memory | |
name | Memory pool name | |
used(M) | Size of the used memory | |
CPU | CPU Usage | CPU usage of the Java process |
Viewing GC Information¶
APM monitors GC metrics. For details about the metrics, see Table 2.
Figure 6 Viewing GC information¶
Metric Set | Metric | Description |
|---|---|---|
GC statistics | Full GC (times) | Number of full GC times in a collection period |
Full GC Duration (ms) | Full GC duration in a collection period | |
Young GC (times) | Number of young GC times in a collection period | |
Young GC Duration (ms) | Young GC duration in a collection period | |
GC Details | GC Type | GC type, which can be major or minor |
GC Cause | GC cause | |
Count | Number of times that GC has occurred | |
Total GC Duration (ms) | GC duration | |
Max GC Duration (ms) | Time consumed by the slowest GC | |
GC Recycler | GC recycler name | |
Slowest GC Details | Details about the slowest GC |
Click the digits in blue (such as those in the Count, Total GC Duration (ms), or Max GC Duration (ms) column) to view the corresponding GC trend graph in a certain period (default: 20 minutes).
On the GC details area, you can view the GC type, GC cause, count, total GC duration (ms), maximum GC duration (ms), GC recycler, and slowest GC details (details and history).
Viewing Threads¶
You can view the thread details of the corresponding instance on APM. For details, see Table 4.
Figure 7 Viewing threads¶
Metric Set | Metric | Description |
|---|---|---|
Thread details | Thread Name | Thread name |
Threads | Number of threads | |
CPU Time (ms) | Thread CPU time | |
Memory (MB) | Memory (MB) | |
Thread Stack | Thread stack |
Click a number in the Threads column to view the trend of the thread in a specified period.
Click Detail in the Thread Stack column to view the thread details.
Click History in the Thread Stack column to view the historical thread stack list.
Viewing Java Methods¶
By default, APM does not monitor Java methods. To monitor them, configure the JavaMethod monitoring item first.
After the configuration is complete, the system monitors the methods and classes of JavaMethod.
On the JVM page, select a target instance and JavaMethod to view details. For details, see Table 5.
Figure 8 Viewing Java methods¶
Metric Set | Metric | Description |
|---|---|---|
JavaMethod | Class | Class |
Method | Method | |
Calls | Number of times that the method is called | |
Avg RT (ms) | Average response time | |
Errors | Number of times that the method fails to be called | |
Max Concurrency | Maximum concurrency of the method | |
Max RT (ms) | Maximum response time of the method | |
0 ms-10 ms | Number of requests with 0 ms-10 ms response time | |
10 ms-100 ms | Number of requests with 10 ms-100 ms response time | |
100 ms-500 ms | Number of requests with 100 ms-500 ms response time | |
500 ms-1s | Number of requests with 500 ms-1s response time | |
1s-10s | Number of requests with 1s-10s response time | |
10s-n | Number of requests with response time longer than 10s |
Click a number (such as those in the Calls or Errors column) to view the trend of the thread in a specified period.