IMemoryContext Class Reference

This class defines an interface for the memory requesters that call MemoryManager's ReserveBlocks method. Since this method can make the requester wait until enough memory is available, these requesters will not be able to respond to a SQLCancel unless they let the memory manager know that they are ready to quit, where the memory manager throws an exception, and lets them quit waiting. More...

Inherits Simba::Support::ThreadSafeSharedObject.

Inherited by StatementMemoryContext, DSIExtDataEngineContext, DSIExtExecutorContext, and DSIExtNoncancelableMemoryContext.

List of all members.

Public Member Functions

virtual MemoryToken GetQuerySpecificID () const =0
 Provides a unique ID for the memory manager to identify different consumers that come from the same query.
virtual simba_uint32 GetQueryTimeOut () const =0
 Returns the time-out value, the query will wait max time-out value on memory and then it throws a memory error if it cannot reserve the requested memory.
virtual const volatile bool & IsCanceled () const =0
 Determines if the cancel has been called on the requester.

Protected Member Functions

 ~IMemoryContext ()
 The context should not be deletable via a pointer to it.

Detailed Description

This class defines an interface for the memory requesters that call MemoryManager's ReserveBlocks method. Since this method can make the requester wait until enough memory is available, these requesters will not be able to respond to a SQLCancel unless they let the memory manager know that they are ready to quit, where the memory manager throws an exception, and lets them quit waiting.


Constructor & Destructor Documentation

~IMemoryContext (  )  [inline, protected]

The context should not be deletable via a pointer to it.


Member Function Documentation

virtual MemoryToken GetQuerySpecificID (  )  const [pure virtual]

Provides a unique ID for the memory manager to identify different consumers that come from the same query.

Returns:
A query specific unique ID.

Implemented in StatementMemoryContext, DSIExtDataEngineContext, DSIExtExecutorContext, and DSIExtNoncancelableMemoryContext.

virtual simba_uint32 GetQueryTimeOut (  )  const [pure virtual]

Returns the time-out value, the query will wait max time-out value on memory and then it throws a memory error if it cannot reserve the requested memory.

Returns:
The time out value in milliseconds.

Implemented in StatementMemoryContext, DSIExtDataEngineContext, DSIExtExecutorContext, and DSIExtNoncancelableMemoryContext.

virtual const volatile bool& IsCanceled (  )  const [pure virtual]

Determines if the cancel has been called on the requester.

Returns:
A reference to the canceled flag.

Implemented in StatementMemoryContext, DSIExtDataEngineContext, DSIExtExecutorContext, and DSIExtNoncancelableMemoryContext.


The documentation for this class was generated from the following file:

Generated on Wed May 17 14:21:15 2017 for SimbaEngine 10.1.3.1011 by simba