dt_inner in the Thompson scheme

[SarahLu-NOAA]

Hello CCPP experts
I'm running UFS SRW v2.2 over NE US (12-km resolution). I try both GFS_v16 and GFS_v17_p8 suites. My SRW with GFS_v17_p8 experiments have very unrealistic results and I'm checking phys namelist. My experiment sets DELTIM to 60 sec. The SRW release has dt_inner hard coded to 150 sec for GFS. Could you please provide a guidance/info on dt_inner. Thanks.

[dustinswales]

@SarahLu-NOAA dt_inner is for subcycling in the Thompson MP scheme, where n_cycles = max(1., dt_physics/dt_inner). I'm not an expert here, but I would expect that this needs to be changed in the SRW app since the timestep is shorter.
As you already mentioned, and demonstrated, it doesn't appear that this is causing the large differences.