Connect

Applicability

Note: For Atlas A2 training product / Atlas A2 inference product , only the Atlas 800I A2 inference server and A200I A2 Box heterogeneous subrack are supported.

Function Description

Establishes a link with the remote HIXL instance.

Prototype

1

Status Connect(const AscendString &remote_engine, int32_t timeout_in_millis = 1000)

Parameters

Example

Click GitCode, select the matching version, and obtain the sample from the examples/cpp directory.

Returns

• SUCCESS: Success.
• PARAM_INVALID: Incorrect parameter.
• TIMEOUT: Link establishment timeout.
• ALREADY_CONNECTED: Duplicate link establishment.
• Other values: Failure.

Exception Handling

None

Restrictions

• This API must be called after the Initialize API is called on the client and server to complete initialization.
• The maximum number of communication links that can be created is 512; creating too many links may lead to OOM errors and performance degradation during KV cache transmission. This restriction applies to the following products:
  • Atlas A2 training product / Atlas A2 inference product
  • Atlas A3 training product / Atlas A3 inference product
• You are advised to set the timeout interval longer than 200 ms. If TLS is enabled, it is recommended that the timeout period be set to a value greater than 2000 ms. Run the following command to query the TLS status:

  hccn_tool [-i %d] -tls -g [host]

• Before calling this API, register all local and remote memories. Otherwise, memories registered after link establishment will not support remote access.
• In container scenarios, you must map the /etc/hccn.conf file into the container or ensure that hccn_tool exists in the default path /usr/local/Ascend/driver/tools. If neither condition is met, you need to add the directory containing hccn_tool to the PATH environment variable. A configuration example is provided below, where hccn_tool_install_path indicates the directory containing hccn_tool.

  export PATH=$PATH:${hccn_tool_install_path}

  This restriction applies to the following products:

  • Atlas A2 training product / Atlas A2 inference product
  • Atlas A3 training product / Atlas A3 inference product
• This API and Initialize must run in the same thread. If you need to switch threads to call this API, first call aclrtGetCurrentContext in Application Development (C&C++) in the thread where Initialize is running to obtain the context. Then, in the new thread, call aclrtSetCurrentContext in Application Development (C&C++) to set the context.