by Reid Smith-Vaniz
You’ve determined that you need to add capacity to your storage infrastructure. Here are some tips on how to pick the right EMC drives to meet your needs.
- Oracle, SQL and DB2 databases all love spindles; consider FC or SAS. Much of the information organizations store is in databases, and system admins need to give users fast access to that information. To deliver that performance, DBAs should ensure their databases are stored on lots of disk drives. It’s better to over-compensate with the number of drives because, in large part, they determine the performance of the storage array. Stay away from SATA drives for your main drives—too slow—and stick with Fibre Channel or SAS. SATA drives; however, may be useful for other applications (also see tip #6 below). If you’ve got the resources, adding SSD drives will boost performance even further.
- Databases like small drives—146GB or 300GB. Instead of buying a 1TB drive, buy multiple 300GB drives. You’ll have more spindles retrieving information faster because they have to travel shorter distances on the drive to fetch it.
- VMWare can use 300GB, 450GB or 600GB. VMWare is typically performance-intensive, and FC or SAS drives in these sizes work best. Try to deploy FC or SAS drives even if you’re in a budget crunch.
- Don’t use SATA for VMWare—you’ll regret it. SATA drives are better for archiving or back-up and don’t offer the performance you need for VMWare.
- Use FC drives for disk clone volumes—performance will suffer if you use SATA. If, for example, you have an Oracle database and want to clone it for testing, don’t use slow SATA drives. Use Fibre Channel or something equivalent to what you have in production so you can have an accurate development, test or QA environment.
- File servers are perfect for SATA drives. File servers are typically slow and don’t need high-speed disk drives, so SATA drives are a sensible, cost-efficient choice.
- Microsoft Exchange should be on FC or SAS drives. Exchange is often an enterprise-class application these days, so you need it to be on a fast disk.
- SSD drives are excellent for high performance apps, however, they’re pricey. SSD drives are great for high-performance applications and work well with auto-tiering technology that puts the applications that need the best performance on the fastest storage, and then flushing them out when they’re not running as hot. That’s a good design, but it requires buying the software and the SSD drives. If you’re considering SSD, you’re probably trying to solve a performance issue, so you need to understand how much of an issue it really is. Are you gigging out and want to buy SSD drives because it’s the latest thing? Could your performance issue be mitigated with an extra tray of drives? You can often get the same performance you’d get from SSD with a tray of 300GB or 146GB drives for a quarter of the price. That not only solves the problem, you get more capacity, because SSD drives are typically around 100GB.
- Disaster Recovery storage arrays need Fibre Channel drives to quickly ingest the replication volumes. If you’re replicating data to a disaster recovery site, you want it to go fast, and FC drives are faster than SATA.
Keep in mind that when you pick an EMC disk drive, it’s important to consider what your current and future workloads are, what your environment looks like, how it’s performing, and more. Be aware that adding drives might also require moving some existing workload around.
The best strategy is to take a holistic viewpoint—look at your SAN infrastructure and connectivity to make sure there’s not a performance issue there or with server hardware, notably with the HBAs or the connections going into the network fabric. It’s important to know which disk drives to pick, and to work with someone who understands your environment so you don’t run into unanticipated issues.