You can view the performance of a job instance that is running, such as the CPU utilization of the JobManager and TaskManagers, the dynamic memory usage of TaskManagers, and the thread usage of TaskManagers. This topic describes how to view the performance of JobManager and TaskManagers of a job instance.

Background information

You can view the performance of JobManager and TaskManagers to identify code errors, such as errors of job code, slow initialization of classes, and a large number of resources occupied by classes. The following table describes the information about the job performance that you can view in the console of fully managed Flink.
Dimension Item Description
JobManager Flame Graph
  • CPU: In most cases, functions that are at the top level of the flame graph and occupy a large width consume more CPU resources. These functions may have performance issues.
  • Alloc: You can view the memory usage that is allocated by different types of classes.
  • Lock: You can view the cause of the decline in the performance of a job. For example, you can check whether the decline is caused by lock contention or deadlock issues.
  • ITimer: You can view the CPU utilization of all threads at each interval when the time intervals among threads are the same.
TaskManagers Flame Graph
Memory Dynamics You can view the memory changes in different memory regions of the Java Virtual Machine (JVM).
Threads Dynamics You can view the details about the threads. You can select threads to sample and analyze the details of the threads.

Limits

  • Only Flink that uses Ververica Runtime (VVR) 4.0.11 or later allows you to view the job performance.
  • You can view only the performance of a job instance that is in the Running state. You cannot view the performance of a historical job instance.

Procedure

  1. Log on to the Realtime Compute for Apache Flink console.
  2. On the Fully Managed Flink tab, find the workspace that you want to manage and click Console in the Actions column.
  3. In the left-side navigation pane, choose Applications > Deployments.
  4. Click the name of the desired job.
  5. Click the Logs tab.
  6. View the performance of JobManager and TaskManagers.
    • Performance of JobManager
      1. On the Running Logs tab, click Job Manager and click Debug. Performance 1
      2. On the Flame Graph tab, view the performance of JobManager.
    • Performance of TaskManagers
      1. On the Running Logs tab, click Task Managers and click the value in the Path, ID column. pathid
      2. Click Debug. Performance 2
      3. View the performance of TaskManagers.