Test "OSDF" and verify the performance and result

With a realistic DA case, test "OSDF" (internal obs data structure) and verify the performance (runtime, memory usage) and result (from obs feedback file).

See the example from Steve Vahl.
To answer your question you asked during the quarterly meeting, here is an example yaml block that shows what you need to add in order to test using the new OSDF (data frame) container for Obs Spaces. Obviously, the last line is the critical one. Hope this helps.

- obs space:
    name: "Radiosonde_1var"
    simulated variables:
    - airTemperature
    obsdatain:
      engine:
        type: H5File
        obsfile: Data/testinput_tier_1/sondes_obs_2018041500_m.nc4
    obsdataout: 
      engine:
        type: H5File
        obsfile: testoutput/sondes_obs_2018041500_m_osdf_frame_cols.nc4
    use data frame container: true

In the current develop code, this is set as 'false' : https://github.com/JCSDA-internal/ioda/blob/develop/src/ObsSpaceParameters.h#L95

After doing some extensive test, this option would be a default option in future.

Start with the YAML example in the issue and the current use data frame container setting in src/ObsSpaceParameters.h. Run the realistic Radiosonde_1var case using the referenced input and output files, then compare runtime, memory usage, and the observation-feedback result. Done means the OSDF behavior is verified and there is enough evidence to decide whether it should become the default.