QUESTION 1: HOW FAST CAN SQL SERVER READ DATA FROM DISK?
You can measure this by doing a full backup to disk, but use the NUL: option:
- BACKUP DATABASE MyDb TO DISK=‘NUL:’
This does a backup, but doesn’t actually write it anywhere, so it’s a measure of how fast the data files can be read from storage. If you run this, know that you’re taking a real backup: this backup can break your differential backups.
Vital follow-up: Sean McCown’s talk on performance tuning for backups. SQL Server backups have a few knobs you can turn, like buffercount, maxtransfersize, and number of files.