How long it takes to Add 400 Orthophotos to a Mosaic Dataset?

[Y_Chau]

I want to create a mosaic dataset with 400 1m pixel size orthophotos. Each image is about 1 GB and 20,000 x 20,000 rows and columns. I created pyramids beforehand. Now I am trying to add these images to a Mosaic Dataset. For hours it just stays at 0% with messages in attached picture. I am using ArcGIS Pro on a 64 GB Xeon processor. Any idea if this will work?

Sincerely

[Robert_LeClair]

A few questions for you: 
1.  Are you adding the mosaics to a mosaic dataset in a file or enterprise geodatabase?
2.  Is the folder of raw images on a shared network drive or on your C: drive?
3.  Is the target geodatabase on your C: drive or a network share?

[Y_Chau]

Hi Robert

1. It is a file GDB.
2. Both mosaic dataset and raw images are on the same drive. 
3. It is not a network drive and not C. Just another partition on the one storage drive.

Thanks

[Robert_LeClair]

Okay - thank you for the details.  Let's try this workflow - instead of adding all 400 raster datasets in one operation, break them into smaller groups - say 50 or 100 - and see if the process completes.  If so, then load another group of 50 or 100.  Repeat the process until all 400 images are added.  What is the result?