Currently, we're moving into the "magic bullet" phase of SATA adoption. Storage administrators have widely recognized their advantages and they are snapping them up. But, like any other storage technology, SATA drives have weaknesses as well as strengths.
Here are some worst practices that minimize the advantages of SATA drives while maximizing the disadvantages.
Because SATA drives are cheap and fast, your storage budget can cover more of them. But the worst thing you can do with SATA drives is to use them as an excuse to continue business-as-usual uncontrolled storage growth.
Process change is almost always harder than switching to a new technology. But you cannot solve a business process problem -- like runaway storage growth -- with a new technology. It may be easier in the short run than enduring the pain of installing a comprehensive, effective storage management strategy, but in the long run it only makes the underlying problem worse.
SATA is not SCSI, nor ATA for that matter. All of them have distinct characteristics that you should consider when selecting drives. You need to think about the application and match the drive technology to it. Otherwise, you're likely to do the equivalent of trying to use ATA drives in applications where you should be using SCSI.
The good news is that this isn't as limiting as using, say, ATA drives inappropriately. Because SATA and SAS can use the same backplane connector, it's easy to replace a SATA drive with a faster SAS drive. In addition, SAS will support more than 16,000 drives on a single backplane connection.
You can get a 250 GB SATA II drive for less than $100. If you're upgrading, it's awfully tempting to replace several 60 GB SCSI drives with one SATA drive to save money.
While you'll save money this way, you may take an unacceptable performance hit. Generally speaking, more spindles mean better performance. Thus, from a performance standpoint, you're almost always better off with data spread across several smaller drives rather than concentrated on one big one.
One of the reasons SATA drives come in higher capacities than SAS or SCSI drives is that they have slower rotation speeds. As a result, your data transfer rates can suffer significantly.
And the big one:
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This was first published in May 2006