Can I use disk size to determine database create size?
If one has a disk allocated to the mdf file, for this example a 500GB disk, will it be good practice to reserve 80% of the disk for the initial database size? Same for ldf being given allocated a 500GB disk. Reasoning for this is to eliminate auto growth completely. Still have it enabled, but only having it in place for that 1% chance of it happening.
For the data, sure. If you know that disk is dedicated to that database, you can allocate all the space. It won't hurt anything. For the log, I'd be concerned with having that large a log file. Assuming your running frequent enough log backups if you're in full recovery, your log file can be quite small. Allocating 300gb for a 300gb database just doesn't seem like we've configured things correctly.