Can mechanical hard drives (HDD) handle SAS 3's 12GB/s throughput? I'm trying to make a cost analysis that requires maximized transfer speeds but can ONLY use HDD (please don't mention SSDs). Maybe I'm misunderstanding the concept of data transfer falling under the category of reading or writing actions. Even if we purchase 15k RPM, will it make use of SAS3? If not, we'll default to SAS 6 GB/s.
21 Answer
It wasn't a typo on my part. SAS/SATA speeds are usually stated in Gigabit per second rather than Gigabyte per second. Further more, as stated, you'd have to look at what you actually want to do and the relevant data sheets.
For instance you might find that an individual HDD only supports a data rate of 0.5 GB/s while reading. That would saturate a 12 Gb/s SAS3 link to ~33%.
But what does the actual use case look like? What does the access pattern of the applications using that drive look like and do you only have a single drive per channel? Define your scenario and afterwards figure out what would satisfy your needs rather than trying to do it the other way around.
