This script will check to see if any SQL Server Agent Jobs are running long.

--
-- Determine How Long Active SQL Server Agent Job Has Been Running
-- http://stackoverflow.com/a/10726791

select
    sj.name as JobName,
    DATEDIFF(minute, sja.start_execution_date, GetDate()) as MinutesRunning
from msdb..sysjobactivity as sja
join msdb..sysjobs as sj
    on sj.job_id = sja.job_id
where sja.stop_execution_date is null -- job hasn't stopped running
  and sja.start_execution_date is not null -- job is currently running
  and sj.name like N'%job_name_here%'
  and not exists(
      -- make sure this is the most recent run
      select 1
      from msdb..sysjobactivity as new
      where new.job_id = sja.job_id
        and new.start_execution_date > sja.start_execution_date);

-- or...

-- Get all jobs... unfiltered.

select sj.name as JobName,
    DATEDIFF(minute, sja.start_execution_date, GETDATE()) as MinutesRunning
from msdb.dbo.sysjobactivity as sja
inner join msdb.dbo.sysjobs as sj
    on sja.job_id = sj.job_id
where CONVERT(date, sja.start_execution_date) = CONVERT(date, GETDATE())
    and sja.stop_execution_date is null;

/* ----------------------------------------------------------------------------

Find Currently Long Running SQL Agent Jobs

This script will check to see if any currently running jobs are running long.

Variables:
    @MinHistExecutions  - Minimum number of job executions we want to consider
    @MinAvgSecsDuration - Threshold for minimum job duration we care to monitor
    @HistoryStartDate   - Start date for historical average
    @HistoryEndDate     - End date for historical average

These variables allow for us to control a couple of factors. First we can focus
on jobs that are running long enough on average for us to be concerned with
(say, 30 seconds or more).

Second, we can avoid being alerted by jobs that have run so few times that the
average and standard deviations are not quite stable yet.

This script leaves these variables at 1.0, but I would advise you alter them
upwards after testing.

Returns: One result set containing a list of jobs that are currently running and
are running longer than two standard deviations away from their historical
average. The "Min Threshold" column represents the average plus two standard
deviations.

Compatiblity: SQL2005, SQL2008, SQL2008R2, SQL2012, SQL2014

Author:  Thomas LaRock, http://thomaslarock.com/contact-me/
Date:    August 19th, 2014
Article: http://thomaslarock.com/2014/08/find-currently-running-long-sql-agent-jobs/

You may alter this code for your own purposes. You may republish altered code as
long as you give due credit.

THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
----------------------------------------------------------------------------- */

declare @HistoryStartDate datetime,
    @HistoryEndDate datetime,
    @MinHistExecutions int,
    @MinAvgSecsDuration int;

set @HistoryStartDate = '19000101';
set @HistoryEndDate = GETDATE();
set @MinHistExecutions = 1.0;
set @MinAvgSecsDuration = 1.0;

declare @currently_running_jobs table(
    job_id uniqueidentifier not null,
    last_run_date int not null,
    last_run_time int not null,
    next_run_date int not null,
    next_run_time int not null,
    next_run_schedule_id int not null,
    requested_to_run int not null,
    request_source int not null,
    request_source_id sysname null,
    running int not null,
    current_step int not null,
    current_retry_attempt int not null,
    job_state int not null
);

--capture details on jobs
insert into @currently_running_jobs
    execute master.dbo.xp_sqlagent_enum_jobs 1, '';

with JobHistData as (
    select job_id,
        date_executed = msdb.dbo.agent_datetime(run_date, run_time),
        secs_duration = run_duration / 10000 * 3600 + run_duration % 10000 / 100 * 60 + run_duration % 100
    from msdb.dbo.sysjobhistory
    where step_id = 0 --Job Outcome
        and run_status = 1 --Succeeded
    ), JobHistStats as (
    select job_id,
        AvgDuration = AVG(secs_duration * 1.),
        AvgPlus2StDev = AVG(secs_duration * 1.) + 2 * stdevp(secs_duration)
             from JobHistData
             where date_executed >= DATEADD(day, DATEDIFF(day, '19000101', @HistoryStartDate), '19000101')
               and date_executed < DATEADD(day, 1 + DATEDIFF(day, '19000101', @HistoryEndDate), '19000101')
             group by job_id
             having COUNT(*) >= @MinHistExecutions
                and AVG(secs_duration * 1.) >= @MinAvgSecsDuration)
     select jd.job_id,
         j.name as JobName,
         MAX(act.start_execution_date) as ExecutionDate,
         AvgDuration as [Historical Avg Duration (secs)],
         AvgPlus2StDev as [Min Threshhold (secs)]
     from JobHistData as jd
     join JobHistStats as jhs
         on jd.job_id = jhs.job_id
     join msdb..sysjobs as j
         on jd.job_id = j.job_id
     join @currently_running_jobs as crj
         on crj.job_id = jd.job_id
     join msdb..sysjobactivity as act
         on act.job_id = jd.job_id
        and act.stop_execution_date is null
        and act.start_execution_date is not null
     where DATEDIFF(SS, act.start_execution_date, GETDATE()) > AvgPlus2StDev
       and crj.job_state = 1 -- comment this line if you want to report on all jobs
     group by jd.job_id,
         j.name,
         AvgDuration,
         AvgPlus2StDev;