Track Java JVM and GC Metrics via Cloud Monitor - Cloud Monitor

After you install an agent for a Java application, Cloud Monitor 2.0 starts monitoring it. On the Instance Monitoring page, you'll see its basic monitoring data, instance garbage collection (GC) details, and Java Virtual Machine (JVM) memory usage.

Prerequisite

An agent is installed for the application.

Try in Playground

Alibaba Cloud Playground provides a demo environment where you can experience the main features of Cloud Monitor 2.0.

Visit the Playground demo environment. By default, you are logged on to the o11y-demo-cn-hangzhou workspace.
In the left navigation pane, choose Application Center > Application Observability > Application Monitoring.
On the Applications page, click an application. Then, click Instance Monitoring.

View in console

Log on to the Cloud Monitor 2.0 console, and select a workspace. In the left navigation pane, choose Application Center > Application Observability > Application Monitoring.
On the Applications page, click an application. Then, click Instance Monitoring.

Instance Monitoring

The Instance Monitoring tab provides dashboard data based on whether the application is deployed in an Elastic Compute Service (ECS) instance or a container cluster, and whether the environment is monitored in Managed Service for Prometheus.

If your application is deployed in a container cluster that is monitored in Managed Service for Prometheus, the data of Managed Service for Prometheus is displayed in the dashboard. For information about how to use Managed Service for Prometheus to a monitor a container cluster, see Monitor an ACK cluster.
If the container cluster is not monitored in Managed Service for Prometheus, make sure that the Application Monitoring agent version is 4.1.0 or later. Then, the data of Application Monitoring is displayed. For information about the agent for Java, see Release notes of the ARMS agent for Java.

ECS instance

In the Quick Filter section, query charts and instances by cluster or instance ID.
In the trend charts section, view the time series of basic monitoring, GCs, and JVM memory.
- Basic monitoring: shows the trend charts of CPU utilization, memory usage, and disk usage in the specified time period. Switch between the average and maximum values from the drop-down list.
- Instance GC: shows the trend charts of full GCs and young GCs in the specified time period. Switch between the number of GCs and the average duration.
- JVM memory: shows the trend charts of used and maximum heap memory within the specified time period from the drop-down list. Switch between the heap memory and non-heap memory.
  Note
  The data collected by Application Monitoring comes from JMX, excluding some non-heap memory areas of Java processes. Therefore, the sum of heap and non-heap memory displayed in Application Monitoring differ greatly from the RES queried by running the top command. For more information, see Details of JVM monitoring memory.
In the instance list section, view instance information, such as the IP address, CPU utilization, memory usage, disk usage, load, number of full GCs, number of young GCs, heap memory usage, non-heap memory usage, and key metrics of each instance defined by the RED Method, including rate, errors, and duration.
In the instance list, you can perform the following operations:
- Click an instance IP address to view the instance details.
- Click Traces in the Actions column to view the trace details of an instance.

Container cluster monitored in Managed Service for Prometheus

In the Quick Filter section, query charts and instances by cluster ID or host IP address.
In the trend charts section, view the time series of basic monitoring, GCs, and JVM memory.
- Basic monitoring: shows the trend charts of CPU utilization and memory usage in the specified time period.
- Instance GC: shows the trend charts of full GCs and young GCs in the specified time period. Switch between the number of GCs and the average duration.
- JVM memory: shows the trend charts of used and maximum heap memory within the specified time period from the drop-down list. Switch between the heap memory and non-heap memory.
  Note
  The data collected by Application Monitoring comes from JMX, excluding some non-heap memory areas of Java processes. Therefore, the sum of heap and non-heap memory displayed in Application Monitoring differ greatly from the RES queried by running the top command. For more information, see Details of JVM monitoring memory.
In the instance list section, view instance information, such as the IP address, used CPU, requested CPU, maximum CPU, CPU utilization (%), used memory, requested memory, maximum memory, memory usage (%), used disk size, maximum disk size, disk usage (%), load, number of full GCs, number of young GCs, heap memory usage, non-heap memory usage, and key metrics of each instance defined by the RED Method, including rate, errors, and duration. Note that if the maximum CPU, memory, or disk size is not configured, - is displayed in place of the CPU utilization, memory usage, or disk usage.
In the instance list, you can perform the following operations:
- Click an instance IP address or click Details in the Actions column to view the instance details.
- Click Traces in the Actions column to view the trace details of an instance.

Container cluster (custom data collection)

In the Quick Filter section, query charts and instances by host IP address.
In the trend charts section, view the time series of basic monitoring, GCs, and JVM memory.
- Basic monitoring: shows the trend charts of CPU utilization and memory usage in the specified time period.
- Instance GC: shows the trend charts of full GCs and young GCs in the specified time period. Switch between the number of GCs and the average duration.
- JVM memory: shows the trend charts of used and maximum heap memory within the specified time period from the drop-down list. Switch between the heap memory and non-heap memory.
  Note
  The data collected by Application Monitoring comes from JMX, excluding some non-heap memory areas of Java processes. Therefore, the sum of heap and non-heap memory displayed in Application Monitoring differ greatly from the RES queried by running the top command. For more information, see Details of JVM monitoring memory.
In the instance list section, view instance information, such as the IP address, CPU utilization, memory usage, load, number of full GCs, number of young GCs, heap memory usage, non-heap memory usage, and key metrics of each instance defined by the RED Method, including rate, errors, and duration.
In the instance list, you can perform the following operations:
- Click an instance IP address or click Details in the Actions column to view the instance details.
- Click Traces in the Actions column to view the trace details of an instance.

Instance details

Instance overview

On the Instance Overview tab, view the number of requests, number of errors, average duration, and slow calls for the application's interfaces.

JVM monitoring

On the JVM Monitoring tab, view the GCs, memory, threads, and files of the instance.

Thread pool monitoring

Agents V4.1.x and later

The Thread Pool Monitoring tab allows you to view various metrics of the thread pools used by the application, including the initialization thread configuration, runtime thread status, and task execution status.

At the top of the tab, filter the thread pools you want to query by thread pool type and name.

View frameworks supported by Thread Pool Monitoring

The Cloud Monitor agent V4.1.x and later supports the following frameworks:

java.util.ThreadPoolExecutor: Apache Tomcat 8 to 9.1, Apache Dubbo, High-speed Service Framework (HSF), Vert.x, and user-defined thread pools.
org.apache.tomcat.util.threads.ThreadPoolExecutor: Tomcat 9.1 +.
org.eclipse.jetty.util.thread.QueuedThreadPool: Jetty.
org.xnio.XnioWorker: Undertow.

The following metrics are collected:

Metric name	Framework	Description
arms_thread_pool_core_pool_size	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+) XnioWorker QueuedThreadPool	The number of core threads, which remains unchanged.
arms_thread_pool_max_pool_size	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+) XnioWorker QueuedThreadPool	The maximum number of threads, which remains unchanged.
arms_thread_pool_active_thread_count	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+) XnioWorker QueuedThreadPool	The number of active threads, that is, the number of threads with tasks being executed.
arms_thread_pool_current_thread_count	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+) QueuedThreadPool	The current number of threads, including the number of active threads and the number of threads that are waiting for task execution.
arms_thread_pool_max_thread_count	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+)	The maximum historical number of threads in the thread pool.
arms_thread_pool_scheduled_task_count	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+)	The number of tasks scheduled in the thread pool.
arms_thread_pool_completed_task_count	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+)	The number of tasks executed in the thread pool.
arms_thread_pool_rejected_task_count	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+) QueuedThreadPool	The number of rejected tasks in the thread pool.
arms_thread_pool_queue_size	ThreadPoolExecutor (JDK) ThreadPoolExecutor (Tomcat 9.1+) XnioWorker QueuedThreadPool	The size of the task queue in the thread pool.

Agents earlier than V4.1.x

The Thread Pool Monitoring tab allows you to view metrics such as the core thread count, current thread count, maximum thread count, active thread count, and task queue capacity of the thread pools used by the application.

View frameworks supported by Thread Pool Monitoring

The agent earlier than V4.1.x supports the Apache Tomcat, HSF, Apache Dubbo, Vert.x, and Undertow frameworks. Among the agent versions, V3.1.x and earlier support Undertow V1.x and V2.x, whereas V3.2.x and later support all Undertow versions.

The following metrics are collected:

Metric description	Metric name
Number of core threads in the thread pool	arms_threadpool_core_size
Maximum number of threads in the thread pool	arms_threadpool_max_size
Number of active threads in the thread pool	arms_threadpool_active_size
Thread pool queue size	arms_threadpool_queue_size
Current size of the thread pool	arms_threadpool_current_size

The agent earlier than V4.1.x supports the SchedulerX framework. The following metric is collected:

Metric description	Metric name
Number of active threads in the thread pool	arms_threadpool_active_size

Connection pool monitoring

Agents V4.1.x and later

The Connection Pool Monitoring tab allows you to view various metrics of the connection pools used by the application, including initialization thread configuration and runtime thread status.

View frameworks supported by Connection Pool Monitoring

The agent V4.1.x and later supports the following frameworks: DBCP ( > 2.0), Vibur DBCP ( > 11.0), c3p0 ( > 0.9.2), Apache Druid, HikariCP ( > 3.0), Jedis ( > 3.0), Lettuce ( > 5.0), Redisson ( > 3.0).

The following metrics are collected:

Metric name	Framework	Description
arms_connection_pool_connection_count	DBCP, c3p0, Vibur DBCP, Druid, Hikaricp, Jedis, Lettuce, Redisson	The number of connections. Connection have two states: Active and Idle.
arms_connection_pool_connection_min_idle_count	DBCP, Jedis, Druid, HikariCP, Lettuce	The minimum number of idle connections, which remains unchanged.
arms_connection_pool_connection_max_idle_count	DBCP, Jedis, Druid, Lettuce,	The maximum number of idle connections, which remains unchanged.
arms_connection_pool_connection_max_count	DBCP, Druid, Vibur DBCP, HikariCP	The maximum number of idle connections, which remains unchanged.
arms_connection_pool_pending_request_count	c3p0, HikariCP, Jedis	The number of blocked connection requests.

Agents earlier than V4.1.x

The Connection Pool Monitoring tab allows you to view the maximum connection count and active connection count of the connection pools used by the application.

View frameworks supported by Connection Pool Monitoring

The agent earlier than V4.1.x supports the OkHttp2 and OkHttp3 frameworks. The following metrics are collected:

Metric description	Metric name
Number of active connections in the connection pool	arms_threadpool_active_size
Number of current connections in the connection pool	arms_threadpool_current_size

The agent earlier than V4.1.x supports the Apache HttpClient framework. The following metrics are collected:

Metric description	Metric name
Number of current connections in the connection pool	arms_threadpool_current_size
Maximum number of connections in the connection pool	arms_threadpool_max_size
Number of waiting queues in the connection pool	arms_threadpool_queue_size

The agent earlier than V4.1.x supports the Apache Druid framework. The following metrics are collected:

Metric description	Metric name
Number of active connections in the connection pool	arms_threadpool_active_size
Maximum number of connections in the connection pool	arms_threadpool_max_size

The agent earlier than V4.1.x supports the HikariCP framework. The following metrics are collected:

Metric description	Metric name
Number of active connections in the connection pool	arms_threadpool_active_size
Maximum number of connections in the connection pool	arms_threadpool_max_size

Host monitoring

On the Host Monitoring tab, view the metrics about CPU utilization, memory usage, disk usage, load, traffic, and packets.

Reference

For more information about Application Monitoring metrics, see Application Monitoring metrics.