Queries causing the most (de)allocations

-- Queries causing the most (de)allocations in tempDB
SELECT TOP 10
    tsu.session_id, tsu.request_id, tsu.task_alloc, tsu.task_dealloc,
    erq.command, erq.database_id, DB_NAME(erq.database_id) AS [database_name],
    (SELECT SUBSTRING([text], statement_start_offset/2 + 1,
        (CASE WHEN statement_end_offset = -1
            THEN LEN(CONVERT(nvarchar(max), [text])) * 2
            ELSE statement_end_offset
            END - statement_start_offset) / 2
        )
        FROM sys.dm_exec_sql_text(erq.[sql_handle])) AS query_text,
        qp.query_plan
FROM
    (SELECT session_id, request_id, 
        SUM(internal_objects_alloc_page_count + user_objects_alloc_page_count) as task_alloc,
        SUM(internal_objects_dealloc_page_count + user_objects_dealloc_page_count) as task_dealloc
     FROM sys.dm_db_task_space_usage
     GROUP BY session_id, request_id) AS tsu
    INNER JOIN sys.dm_exec_requests AS erq ON tsu.session_id = erq.session_id AND tsu.request_id = erq.request_id
    OUTER APPLY sys.dm_exec_query_plan(erq.[plan_handle]) AS qp
WHERE tsu.session_id > 50 AND database_id >= 5
ORDER BY tsu.task_alloc DESC
GO