SQL Server 2012 Extended Events wait_info vs 2008 R2

Question

Just starting to play with EE in 2012 and was working through a demo that didn't quite work out on 2012 but worked fine on 2008 R2. The demo was on tracing wait stats and it failed due to differences in the data columns that are available between the versions.

SELECT *
FROM sys.dm_xe_object_columns
WHERE [object_name] = 'wait_info'

In 2008 R2 the above allows tracing of wait_type, opcode, duration, max_duration, total_duration, signal_duration and completed_count.

In 2012 all I can see is wait_type, opcode, duration and signal_duration.

There's nothing critical here, just finding my way but am trying to understand if and why those columns have indeed been removed from the new version (I can find no documentation to support that) and are they now untraceable or moved elsewhere?

Answer 1

Those columns were removed because they are the exact same output that you get aggregated from sys.dm_os_wait_stats and they don't add any additional value to the event when it fires. This was requested to make the event more lightweight back in the 2008 timeframe on Connect. I can try to find that Connect item if necessary, but those columns don't really belong with the point in time wait_info event generating for the beginning or ending of a wait in the engine.