text: 
  -- Works in SQL Server 2014
  
  SELECT session_id as SPID,
  command,
  a.text AS Query,
  start_time,
  percent_complete,
  dateadd(second,estimated_completion_time/1000, getdate()) as estimated_completion_time
  FROM sys.dm_exec_requests r CROSS APPLY sys.dm_exec_sql_text(r.sql_handle) a
  WHERE r.command in ('BACKUP DATABASE','RESTORE DATABASE') 
  
  -- remove or change above to monitor other statements than BACKUP/RESTORE
  