Insert tasks and delete tasks will be pushed into _DmTaskQueue_.
If a _insertTask_ is enqueued, _Enqueue(task \*task)_ will set _Ts_, _ReqId_, _ProxyId_, _SegIdAssigner_, _RowIdAllocator_, then push it into _queue_. The _SegIdAssigner_ and _RowIdAllocator_ will later be used in the task's execution phase.
If an _insertTask_ is enqueued, _Enqueue(task \*task)_ will set _Ts_, _ReqId_, _ProxyId_, _SegIdAssigner_, _RowIdAllocator_, then push it into _queue_. The _SegIdAssigner_ and _RowIdAllocator_ will later be used in the task's execution phase.