Some of you read my post on drive performance, 'How fast are your drives?,' and have wondered if investing in a 6Gb/s SAS storage infrastructure makes sense for your environment. Traditional SAS systems have a transfer rate of 3Gb/s, so the new HP 6Gb/s SAS drives and Smart Array controllers have doubled the available bandwidth of storage subsystems.
Given that 6Gb/s refers to the system throughput or the speed at which data travels among the components of the storage subsystem (the drive, controller, server backplane, and/or SAS expander and JBOD), will your system performance really improve? Well, if your environment consists of a small number of storage devices and your I/O workload is 40% or less, you probably won't see any benefits beyond generational improvements (e.g. performance and technology improvements that happen over time). In such environments, the bottleneck may actually be the speed at which bits can be moved to (from) the hard disk platters from (to) the hard disk's integrated controller and the fast transfer among storage devices may be "wasted."
However, if you're running multi-device, storage-intensive applications, such as video streaming, server virtualization, or real-time backup systems, you'll want to make sure your system doesn't saturate as often and pumping data through the system faster will help keep up with your heavy I/O demands.
If you're running a ProLiant G6 server and have a 6Gb/s SAS storage infrastructure, let's hear what kind of application you're running.
The experts agree the new SAS interface is technically more robust than current interface technologies. When it comes to system performance, the benefits of 6G SAS technology can be seen in applications which aggregate multiple components, resulting in higher bandwidth for the whole system. Storage-intensive, high I/O applications such as video streaming, backups, large databases, high online transactions, and virtualization will benefit from the higher throughput of storage and other system devices.
But keep in mind: if you are looking to achieve a 6Gb/s line rate, you need an end-to-end 6G infrastructure, including server backplanes, HBAs and storage controllers, as well as drives. If any of the components of a storage subsystem operate at different data transfer rates, the system bandwidth will be negotiated down to an acceptable level for all components. The good news is that you don’t have to upgrade your whole infrastructure at once. The new HP 6G SAS drives that launched on March 30 are backward (hmm…and sideways?) compatible with 6G/3G SAS and 3G/1.5G SATA drives.
So, the 6G SAS drives have advanced features, improve performance, and work with your current hardware. It sounds like your environment can benefit from 6G SAS drives.
With double the data rate of traditional 3Gb/s SAS drives, the new 6Gb/s SAS drives bring you an opportunity to break through the system bottlenecks of the past. Ramping up to 6Gb/s means greater system bandwidth than before.
Speaking of data rate, let's quickly dispel the confusion between 'data rate' and 'RPM.' Data rate or line rate is the speed at which data travels from the disk to the HBA or storage controller; while RPM is the rotational speed of the drive platters (in rotations per minute). One more thing - data transfer speed is not influenced by access time or latency.
On March 30, HP introduced the 146/300GB 6G SAS 10K 2.5in DP ENT drives (the first two 6G SAS drives) to the portfolio. If you have HP DL360 G6, DL380 G5, or BL460c G6 servers in your environment, it's easy to take full advantage of these high-performing, dual port 6Gb/s SAS drives.
Note that for a storage subsystem to truly operate at 6Gb/s, the drive, the HBA or storage controller, and the server backplane must have 6Gb/s data transfer rates, or the system will negotiate down to an acceptable level for all components. Refer to teh server and HBA/controller technical specifications for transfer rate details.
Have you been waiting for higher capacities on your 2.5-inch small form factor (SFF) drives? HP will launch the 300GB 3G SAS 10K SFF Enterprise Drive shortly. With this drive you will get more for less:
- More storage capacity than any other SFF drive in the market
- 50% less power usage in 70% less space than 3.5-inch 15K drives.
This drive is an enterprise drive, ideally suited for those environments for servers and storage solutions running business critical, high I/O and heavy workload applications. They provide the high performance and maximum reliability (about 3.5 times that of Entry Drives) required by
- Near 24/7 operating environments
- Large databases
- High-transaction applications such as e-mail, ERP, and CRM
- Real-time customer facing environments
Being the leader in the industry when it comes to small form factor SAS drives, HP is known to ship more small form factor drives than any other OEM. With integrated HP technology, such as Systems Insight Manager, SmartStart and HP Flash utilities, you can take advantage of pre-failure alerts and avoid costly data loss and un-planned downtime. HP also provides a pre-failure warranty allowing you to replace a degrading drive before it actually fails. To further simplify support processes, HP drives are covered under the server CarePack.
To find out more about HP drives, click here.