Network jitter

Limitations

• Regions

• Operating systems

  Architecture	Operating system
  x86 architecture	Rocky Linux 9.5 Rocky Linux 9.1 Ubuntu 20.04 Alibaba Cloud Linux 3 Container Optimized Edition Rocky Linux 8.8 Ubuntu 22.04 Alibaba Cloud Linux 3 Pro Alibaba Cloud Linux 2/3 CentOS 7.6 or later, or CentOS 8 Anolis OS 7/8 Ubuntu 24.04
  ARM architecture	Alibaba Cloud Linux 3 Pro Alibaba Cloud Linux 3

Use cases

The network jitter diagnosis feature supports the following scenarios.

• Determine if network jitter is caused by an application that is slow to receive data packets.

• Determine if network jitter is caused by slow data packet processing during kernel softirq handling.

• Determine if network jitter is caused by slow data packet processing in the kernel's qdisc queue.

Prerequisites

• If you use a RAM user, make sure that the Alibaba Cloud account (primary account) has granted the RAM user the AliyunECSReadOnlyAccess, AliyunSubManageFullAccess, and AliyunSysomFullAccess system policies.

• The console permissions are activated.

  The first time you log on to the Operating System Console, click Activate Service to activate the console service.

Procedure

1. Go to Operating System Console.

2. In the left-side navigation pane, click System Diagnosis.

3. In the upper part of the left-side navigation pane, select the region in which the target instance resides.

   

4. Select Network Diagnosis from the Diagnosis Type list and Network Jitter from the Diagnosis Item list. Then, select the target Instance ID and Diagnosis Duration, and click Run Diagnosis.

   Note

   If SysOM is not installed, the system automatically installs SysOM on the target ECS instance and then starts the diagnosis after you click Run Diagnosis.

5. In the Diagnosis Records section, click View Report.

Diagnosis report

• Basic information

• This section lists basic diagnostic information, including the instance ID (resource ID), diagnosis item, diagnosis report ID, and start time.

• Diagnosis conclusion

  This section provides the diagnosis conclusion and identifies the primary cause of the network jitter.

• Diagnosis suggestion

  This section provides recommendations based on the diagnosis results to help you resolve the network jitter.

• Diagnosis details

  This section displays detailed data from the diagnosis and explains the key fields.

  • Time: The time when network jitter was detected.

  • Latency (ms): network latency caused by the jitter.

  • Details: Information about the network jitter, including the associated process and socket.

  • Type: The classification of network jitter, based on its origin (for example, application, softirq, or qdisc).