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RTM Limitations

Last updated 2022/06/28 08:57:08

This page provides a brief overview of the limitations of the Agora RTM Web SDK, including API call limit, string size, encoding, and more.

Channel message limit

The Agora RTM SDK does not have a limit on the number of concurrent online users. However, Agora has the following recommendations on the maximum number of channel messages per second for a single channel:

Concurrent online users in a single channel Number of channel messages per second
< 1,000 < 200
≥ 1,000 and < 10,000 < 100
≥ 10,000 < 30

If the number of messages per second exceeds the recommended values, latency can increase significantly and may also cause the following issues:

  • The user cannot send or receive messages.
  • The user always stays in the RECONNECTING state or keeps switching between the CONNECTED state and the RECONNECTING state. For other users, the current user may appear offline.

Channel member limit

Agora provides customized service to increase the number of messages per second without affecting latency or stability. Please contact support@agora.io for more information.

API call limit

The call limit is for one RtmClient instance. If an operation corresponds to multiple methods, the number of the method calls of an operation equals the sum of the method calls of all corresponding methods in a specific time frame.

We do not recommend increasing the call limit by creating multiple RtmClient instances.
Function Method Call limit
Log in to the Agora RTM system login Two calls per second
Retrieve member count of specified channels getChannelMemberCount One call per second
Join the same channel each time1 join Two calls every five seconds
Join a different channel each time1 join 50 calls every three seconds
Send messages
  • sendMessageToPeer
  • sendMessage
    		•  180 calls every three seconds
    Retrieve a member list of the channel getMembers Five calls every two seconds
    Renew the Token renewToken Two calls per second
    Query the online status of the specified users queryPeersOnlineStatus 10 calls every five seconds
    Set user attributes
  • setLocalUserAttributes
  • addOrUpdateLocalUserAttributes
  • deleteLocalUserAttributesByKeys
  • clearLocalUserAttributes
    		•  10 calls every five seconds
    Get user attributes
  • getUserAttributes
  • getUserAttributesByKeys
    		•  40 calls every five seconds
    Set channel attributes
  • setChannelAttributes
  • addOrUpdateChannelAttributes
  • deleteChannelAttributesByKeys
  • clearChannelAttributes
    		•  10 calls every five seconds
    Get channel attributes
  • getChannelAttributes
  • getChannelAttributesByKeys
    		•  10 calls every five seconds

    String size

    Supported browsers

    See Supported Browsers.

    Unicode support

    Supports channel and peer-to-peer messages, invitation content, and invitation response in UTF-8 only.

    Miscellaneous

    • Notifications of a member joining or leaving the channel are automatically disabled when the number of channel members exceeds 512. Agora recommends that you call the Gets channel events RESTful API from your server to get the notifications of channel events.
    • The current version supports querying the online status of up to 256 users.
    • You can subscribe to the online status of up to 512 users in one method call, and you can subscribe to the online status of up to 512 users.
    • Attribute settings in one user attribute operation must not exceed 16 KB in size. Attribute settings in one channel attribute operation must not exceed 32 KB in size. Each attribute (key/value pair) must not exceed 8 KB in size. The number of key/value pairs you set in one channel attribute operation must not exceed 32.
    • Each file or image you upload to the Agora server stays for 7 days. The corresponding media ID also stays valid for seven days.
    • Each file or image to upload must not exceed 30 MB.
    • Each client instance can only support up to 9 upload and download processes at the same time.