The VARIABLES section provides an overview of global and local variable assignments: 

In the Locals section, it is also possible to check performance counters that are related to code execution:

In particular, it is possible to measure the following:

• Current SQL latency (ms): When the debugger hits a breakpoint, the Dynamics 365 Business Central Server service will send a probing SQL statement to the Azure SQL database and keep track of how long it takes to receive an answer. This information is helpful if the sandbox node for the tenant has healthy latency or there are infrastructure issues.
• Number of SQL executes: The total number of SQL statements executed in the session since the debugger was started.
• Number of SQL row reads: The total number of database rows read since the debugger was started.
• Top-10 long-running queries: Expanding the Last Executed SQL Statements section, you might observe up to 10 SQL Server statement entries (numbered from 0 to 9). The statements represent the 10 least performant queries, in terms of duration, that have been executed since the session started up, to the first breakpoint hit. These are defined by the following elements:
  • Statement: The T-SQL statement executed.
  • Execution time (UTC): A timestamp defining when the SQL statement was executed.
  • Duration (ms): The duration of the total execution time of the SQL statement. It's useful to analyze this if there are some missing indexes when developing extensions.
  • Rows read: Shows the approximate number of rows read by the SQL statement. It might be useful when looking for missing filters when developing extensions.