Note that Tempdb contention refers to a bottleneck for threads trying to access allocation pages that are in-memory; it has nothing to do with I/O.
The grid contains the following columns:
The SQL Statement responsible for causing the contention.
ID of the session executing the SQL Statement.
The ID is hyper-linked to the same session on the SQL Activity drilldown | Sessions page.
The type of wait that SQL Server has recorded and which is preventing a current request from being executed.
The total wait time in milliseconds spent waiting.
The ID of the session that is blocking the request.
The ID of the resource being waited on.
The ID of the page being waited on.
The type of page being waited on - GAM (Global Allocation Map) or SGAM (Shared Global Allocation Map) or PFS (Page Free Space)
The application executing the SQL Statement.
The name of the Windows server hosting the SQL Server instance.
The SQL Server login name for this session.