Starting in 2009, IBM has been enabling IBM i to run with Solid State Drives (SSDs), and in 2010 the options will only get better. But first, let's take a look at SSDs in general.
A traditional hard disk drive (HDD) has the familiar spinning magnetic disk with an arm that moves back and forth over the surface to read the data. Over the years, HDDs have gotten more capacity, faster, cheaper, and more efficient, and yet, they are absolutely trounced by SSDs when it comes to speed. In a 40-yard dash, think kitten vs. cheetah.
The reason? SSDs are like big slabs of Flash memory--no moving parts. They can drive tens of thousands of I/O operations per second (IOPS) vs. hundreds of IOPS for traditional HDDs. Got an HDD bottleneck? SSDs can eliminate it. Small capacity SSDs can be commonly found in cheap netbooks where the speed can help hide low-end processors; in high-end notebooks, SSDs can readily be found up to 256GB--but for a steep extra cost ramping to well over $500. For most consumers, the brilliant speed and durability of SSDs simply aren't worth the higher cost--which is why most enterprises haven't deployed SSDs with server solutions yet either.
Lower Prices, Better Options, Fast Results
Of course, some businesses are installing enterprise-grade SSDs in their data centers to good effect--they're just mixing and matching workloads to the SSDs.
"SSD uptake is increasing," notes Charles King, principal analyst for Pund-IT. "The cost of SSDs have dropped about 40 percent over the last 12 months. What we've been seeing, like any new storage technology, is that you pay a premium if you need it, and then it becomes increasingly commoditized and becomes a more viable option for a wider variety of use cases."
Today, even though SSDs are rapidly getting cheaper, they're still quite a bit more expensive than traditional HDDs--even when a company has to buy many HDDs to maximize I/O performance. Typically, organizations like banks or the hospitality industry that need to have fast access to data on-hand the moment a customer calls will short-stroke HDDs by placing data only a small percentage of the available capacity, King explains. SSDs, on the other hand, can hold a much larger percentage of the available capacity and retain blistering throughput. So, where an organization might have hundreds of HDDs, only dozens of SSDs could get the job done faster, with a much smaller physical footprint.
In addition to the smaller footprint, companies can achieve energy savings--no disks need to keep spinning for SSDs.
Hot and Cold Data
To take advantage of SSDs without busting the budget, companies are using SSDs only for their "hot" data--the data they need fast access to. Warmer data gets shuffled off to high-performing HDDs, while cold data gets moved to slower and cheaper HDDs. King says that some of these strategies can result in energy efficiency gains of 30 percent while increasing overall system performance.
IBM is promoting its recent experience with Associated Bank-Corp, a diversified bank holding company headquartered in Green Bay, Wisconsin. Associated Bank-Corp runs on IBM Power Systems with IBM i, and it wanted to upgrade storage in its IBM Power Systems-based computing environment and complete its end-of-day workload in three hours instead of four-plus. Would the promise of SSD speed help?
In conjunction with the IBM Power Systems Benchmark Center, the bank installed 72 serial-attached SCSI (SAS) drives, ran a test, then added 8 SSDs to the mix. The 72 SAS drive baseline test ran the daily workload in 4 hours and 22 minutes. And the 72 SAS drives with the 8 SSDs? Two hours and 43 minutes. Better yet, when the bank cut the number of SSDs to just four and the number of SAS drives to 60, the job took only five minutes longer.
Any way you look at it, those are pretty impressive gains made through new storage technology.
Of course, if your business has more time available than a need for speed, SSDs could be a moot point.
IBM in Action
IBM is currently offering 69 GB SSD drives that plug into a standard SAS disk bay slot and is controlled by a SAS controller (5904, 5906, 5908). The SSD is offered in two form factors, a 3.5-inch (#3587) and an SFF (#1909). The 3.5-inch SSD is used in the #5886 EXP 12S Disk Drawer and is controlled by the PCI-X 1.5GB Cache SAS RAID adapter. The SFF SSD is also used in Power 520/550 System base SFF slots and is controlled by the embedded controller.
Also, IBM i 5.4 and 6.1 Storage Manager can maximize the impact of SSDs, and new trace and balance commands can move hot data to SSDs. Plus, some system-critical, high-use objects can be automatically placed on the faster SSDs.
In addition to previously available IBM i support for SSDs installed in I/O drawers, IBM this fall introduced IBM i support for SSDs installed in SANs and installed behind VIOS--this is important because it lets IBM i recognize SSDs as being SSDs, which makes it possible to optimize the use of the SSD.
In order to take advantage of the newest SSD support for IBM i, you'll need to be on the latest releases of IBM i. For example, IBM i 6.1.1 is required for the new SSD VIOS support (basically, there's a variety of new storage options available from IBM these days--some that is supported by older releases and some that needs newer releases--so you'll have to pay close attention, which shouldn't be a problem for companies interested in SSDs anyway).
Meanwhile, how can a customer be sure an SSD investment will pay off? IBM is offering a new SSD Analyzer Tool, which helps you determine if SSDs will provide benefits of significance. For more detail, check out the link in the sidebar.
More on the Way
Later this year--think about the May time frame surrounding the COMMON conference--IBM i storage management will further leverage SSD technology by automatically moving data that is accessed most frequently to SSDs--this will be designed to help clients improve application performance. Right now, customers can move hot data to SSDs for maximum throughput, but IBM is looking to automate this--yeah, that's right, automate. Wow. For some customers, this could be quite handy. You can imagine some situations where SSDs could lead to snappy improvements in application response times, which could in turn lead to happier end users, if not increased productivity.
Sidebar: Further Reading
- Performance Value of Solid State Drives using IBM i
http://www-03.ibm.com/systems/resources/ssd_ibmi.pdf
- SSD Analyzer Tool for IBM i (V5R4 and V6R1)
http://www-03.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/PRS3780
- Power Systems Technical Exchange - SSDs for IBM i presentation
http://www-03.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/PRS3825
- Associated Bank-Corp Case Study QuickView
ftp://ftp.software.ibm.com/common/ssi/pm/ab/n/poc03026usen/POC03026USEN.PDF
- Accelerated Memory Production Offers New SATA-II SSD
http://systeminetwork.com/article/accelerated-memory-production-offers-new-sata-ii-ssd
- Texas Memory Systems Earns IBM Certification for Solid State Disks
http://systeminetwork.com/article/texas-memory-systems-earns-ibm-certification-solid-state-disks
Chris Maxcer is news editor for
System iNEWS (chris.maxcer@penton.com). “In addition to greater speed, SSDs promise greater resilience,” Chris says. “No moving parts--who doesn’t love that?”