@Matthew Monday: We strongly recommend using just one storage pool. (E.g. In the presence of multiple pools, features like auto-pooling automatically disable themselves.) I am guessing you have SSD and HDD, and the SSD will be used for Storage Spaces Direct caching. I just asked Ned Pyle, the SR PM, and he tells me that you can create the log virtual disk on that same pool (HDD with SSD cache) and it's absolutely supported. The only caveat is, obviously all-flash would be faster. :) I hope this helps!