data as single domain in VisIt, no subsets
When I open the 'Controls/Subset' window in VisIt, I find that the whole SDF output is marked as a single domain, despite being quite large (100's of GB) and coming from a computation on 100's of cluster nodes. This is quite surprising, because with a single domain one cannot use parallel upload and processing capabilities of VisIt, as outlined in the VisIt manual (https://visit-sphinx-user-manual.readthedocs.io/en/latest/Subsetting/Using_the_Subset_Window.html). As a result it is impossible to process large (~TB size) SDF files in VisIt, and for smaller ones there is little improvement in performance when using multiple cores for the task. There are various tricks to restrict the processed domain, but even then it would be useful to have the possiblity of manually turning on/off some subdomains and species, not to mention the speedup due to parallelism. Why then these subdomains and species are not explicitly visible in the SDF file from the beginning?