Each time SQL Server Agent starts, it creates a new session. SQL Server Agent uses sessions to preserve the status of jobs when the SQL Server Agent service is restarted or stopped unexpectedly. Each row of the syssessions table contains information about one session. Use the sysjobactivity table to view the job state at the end of each session.
This table is stored in the msdb database.
ID of a SQL Server Agent session.
Date and time that the SQL Server Agent service was started for this session.