Session

Product Support Status

Product	Support Status
Atlas A3 Training Series Products/Atlas A3 Inference Series Products	√
Atlas A2 Training Series Products/Atlas A2 Inference Series Products	√

Module Import

from ge.session import Session
from ge.error import GeError

Functionality Description

Session class manages graph compilation and execution sessions. Supports synchronous execution (run_graph) and asynchronous execution (run_graph_with_stream_async). In asynchronous execution scenarios, custom memory allocator can be registered through register_external_allocator. Does not support copy and deep copy.

Class Definition

class Session:
    def __init__(self, options: Optional[dict] = None) -> None
    def add_graph(self, graph_id: int, graph: Graph, options: Optional[dict] = None) -> None
    def remove_graph(self, graph_id: int) -> None
    def run_graph(self, graph_id: int, inputs: List[Tensor]) -> List[Tensor]
    def run_graph_with_stream_async(self, graph_id: int, stream: int, inputs: List[Tensor]) -> List[Tensor]
    def register_external_allocator(self, stream: int, allocator: Allocator) -> None
    def unregister_external_allocator(self, stream: int) -> None

Function Description

__init__

def __init__(self, options: Optional[dict] = None) -> None

Functionality Description: Creates session instance, can pass configuration dictionary for initialization. If no configuration passed, uses default configuration to create session.

Parameter Description:

Parameter	Type	Required/Optional	Description
options	Optional[dict]	Optional	Session configuration dictionary, key-value pairs are string type. When not passed, uses default configuration to create session.

Return Value Description: No return value.

Constraint Description:

• options must be dict type or None, passing other types will throw TypeError.
• When session creation fails, will throw GeError, exception information contains GE internal error information and interface context.
• Session does not support copy and deep copy, attempting to copy will throw RuntimeError.

add_graph

def add_graph(self, graph_id: int, graph: Graph, options: Optional[dict] = None) -> None

Functionality Description: Adds graph to session, supports passing additional compilation options.

Parameter Description:

Parameter	Type	Required/Optional	Description
graph_id	int	Required	Unique identifier of graph, used to distinguish different graphs in session.
graph	Graph	Required	Graph object to be added.
options	Optional[dict]	Optional	Graph compilation configuration dictionary, key-value pairs are string type. When not passed, uses default configuration.

Return Value Description: No return value.

Constraint Description:

• graph_id must be int type, otherwise throws TypeError.
• graph must be Graph type, otherwise throws TypeError.
• options must be dict type or None, otherwise throws TypeError.
• When adding graph fails, will throw GeError, exception information contains GE internal error information and interface context.

remove_graph

def remove_graph(self, graph_id: int) -> None

Functionality Description: Removes specified graph from session.

Parameter Description:

Parameter	Type	Required/Optional	Description
graph_id	int	Required	Unique identifier of graph to be removed.

Return Value Description: No return value.

Constraint Description:

• graph_id must be int type, otherwise throws TypeError.Constraint Description:
• graph_id must be int type, otherwise throws TypeError.
• When graph removal fails, throws GeError, exception message includes GE internal error message and interface context.

run_graph

def run_graph(self, graph_id: int, inputs: List[Tensor]) -> List[Tensor]

Functionality Description: Synchronously execute specified graph, pass input tensor list, return output tensor list.

Parameter Description:

Parameter Name	Type	Required/Optional	Description
graph_id	int	Required	Unique identifier of graph to execute.
inputs	List[Tensor]	Required	Input tensor list, all elements in list must be Tensor type.

Return Value Description:

Return Value Type	Description
List[Tensor]	Output tensor list after graph execution.

Constraint Description:

• graph_id must be int type, otherwise throws TypeError.
• All elements in inputs must be Tensor type, otherwise throws TypeError.
• When graph execution fails, throws GeError, exception message includes GE internal error message and interface context.

run_graph_with_stream_async

def run_graph_with_stream_async(self, graph_id: int, stream: int, inputs: List[Tensor]) -> List[Tensor]

Functionality Description: Asynchronously execute graph on specified stream, pass input tensor list, return output tensor list. Output tensor memory allocation prioritizes using external allocator registered through register_external_allocator; if no external allocator registered, GE will automatically use built-in allocator.

Parameter Description:

Parameter Name	Type	Required/Optional	Description
graph_id	int	Required	Unique identifier of graph to execute.
stream	int	Required	Stream address, used to specify stream for asynchronous execution.
inputs	List[Tensor]	Required	Input tensor list, all elements in list must be Tensor type.

Return Value Description:

Return Value Type	Description
List[Tensor]	Output tensor list after graph execution.

Constraint Description:

• graph_id must be int type, otherwise throws TypeError.
• stream must be int type, otherwise throws TypeError.
• inputs must be list type and all elements must be Tensor type, otherwise throws TypeError.
• If this stream has no registered external allocator and default allocator registration fails, throws GeError, exception message includes GE internal error message and interface context.
• When graph execution fails, throws GeError, exception message includes GE internal error message and interface context.

register_external_allocator

def register_external_allocator(self, stream: int, allocator: Allocator) -> None

Functionality Description: Register external memory allocator for specified stream, used to manage device memory allocation in asynchronous execution scenarios.

Parameter Description:

Parameter Name	Type	Required/Optional	Description
stream	int	Required	Stream address.
allocator	Allocator	Required	External memory allocator instance, must be subclass instance of Allocator abstract base class.

Return Value Description: No return value.

Constraint Description:

• stream must be int type, otherwise throws TypeError.
• allocator must be Allocator instance, otherwise throws TypeError.
• When registration fails, throws GeError, exception message includes GE internal error message and interface context.
• Re-registering same stream will overwrite previous external allocator.

unregister_external_allocator

def unregister_external_allocator(self, stream: int) -> None

Functionality Description: Unregister external memory allocator registered on specified stream.

Parameter Description:

Parameter Name	Type	Required/Optional	Description
stream	int	Required	Stream address.

Return Value Description: No return value.

Constraint Description:

• stream must be int type, otherwise throws TypeError.
• When unregistration fails, throws GeError, exception message includes GE internal error message and interface context.