Solid-state disk (SSD) has grabbed a lot of attention lately, but analysts say it's still a niche technology that is specialized, high-priced and far from ready to supplant the bedrock that is hard disk drives. But with the promise of rocket I/O performance, some users are ignoring the cost and plopping down the big bucks anyway.
For example, Danish jewelry and accessory manufacturer Pilgrim a|s was able to solve major database user response time issues by installing 64GB of flash memory from Texas Memory Systems Inc. The flash storage, in the form of a RamSan-400 appliance, gave the company a twentyfold improvement in IOPS -- from 1,200 I/O per second with its old system to 24,000 I/O per second. But the price for a RamSan system with 64GB of flash is $72,000 retail.
Pilgrim uses Microsoft Corp.'s Dynamics AX (formerly Microsoft Axapta) with Microsoft SQL Server 2005 Enterprise for everything from manufacturing and inventory control to accounting and business intelligence. Pilgrim said the old system was bogging down because of an IBM DS4300 storage array that was unable to keep up with intense, random I/O during peak business hours.
“The RamSan is amazingly easy to install, much easier than other Fibre Channel storage devices we have tested,” said Anders Schack Petersen, a systems administrator for Pilgrim. Pilgrim plans to upgrade to 128GB in its RamSan SSD system over the next two years.
What most users don't know about SSD relates to how versions based on nonvolatile NAND flash memory are increasingly finding their way into laptops and PCs, and how Microsoft Vista compatibility with the emerging technology is expected to give a major boost to hybrid hard disk drives, which combine spinning disk with SSD (see "New hybrid drives promise faster Vista laptops, PCs, servers ").
Today, most SSD is actually manufactured with volatile, CMOS RAM-based components and built-in battery backup providing huge, 4X and even 10X performance improvements for companies that live or die based on their ability to perform high-speed database transactions.
John Rydning, research manager for hard disk drives at IDC in Framingham, Mass., recently co-authored a study entitled "Solid State Disks: Is Future Disruption on the Horizon? " Although he acknowledges the benefits SSDs are offering to a very limited user audience, Rydning also says there are some caveats on the subject of their high-end performance.
"There are a certain percentage of files that need very fast access. Anywhere from one to five percent of all files for a given server application represent a large percentage of all the I/O activity. Those are the files that are suitable for SSD storage," he says.
With data center capacity requirements growing at a rate of 50% per year, Rydning points out that companies are trying to meet that demand as inexpensively as possible. Expense is often what leaves SSD on the outside looking in because deploying it widely "would be just plain cost-prohibitive," he says. "At this point in time, many SSDs are very expensive and are used mainly as server accelerators, or in rugged applications demanded by military/industrial
customers."
Rydning acknowledges that SSD is now being developed and launched for mainstream PCs, and these flash-based products will likely have quite different price-points than existing SSDs. So-called hybrid disks (flash/spinning disk) for PCs and laptops tout a 50% increase in boot times. "Still, on a price per GB basis, even these newer SSDs will be much higher priced than hard disk drives," he says.
Samsung Corp. said 32GB of flash memory will likely add $700 or more to the price of a notebook. And, Sony's UX90 ultramobile PC with 16GB of flash memory drive retails for $1,805 -- $343 more than a unit with a standard 30GB hard disk. SanDisk Corp. recently announced shipment of its 32GB solid state disk drive and said end users should expect $600 premium in laptops for the flash memory. The suggested retail price is $350 for the SanDisk SSD.
But, there is also strong evidence to suggest that NAND memory is rapidly becoming more affordable. Toshiba Corp. recently announced it expects flash chips to be 70% less expensive by the end of March than they were a year ago. At the same time, NAND manufacturer Hynix Semiconductor Inc. said it expects prices to fall by one-third in the current quarter alone (see "64GB flash for $120? Say goodbye to hybrid disks ").
Microsoft's recently released Vista platform includes a feature that allows SSD to be used in conjunction with a PC's hard disk. Vista's Ready Drive function enables the operating system to boot certain portions of the boot-up sequence from flash memory, which provides faster read access times than a hard disk drive, thus expediting the boot-up process. Vendors such as Samsung and SanDisk Corp. are introducing NAND flash drives for standard PCs that were previously designed for use in ruggedized versions.
Despite these low-end operating system enhancements, however, it is the server-based transactional database segment where SSD is achieving eye-popping performance gains and rapid ROI.
Financial firm sees 10X performance increase
Driven by an intense in-house database application tied to rapidly changing stock market data, a financial firm in the Midwest initially responded to the need for extremely fast disk I/O by throwing faster servers and different versions of RAID at the problem. According to a senior systems engineer at the firm, which asked not to be named, when that tactic didn't work the firm upped the ante by spending $7,000 to beef up a server with 32GB of memory in an effort to create a large, virtual RAM drive. The SSD RAM was supposed to help the firm gain control of the application that tracks stocks and attempts to make calculated real-time decisions based on the flow of the market. The result was less than a success.
"It was significantly faster than what we were doing before, but it still wasn't getting us the results we needed," the engineer says. "We wanted more speed. I don't know how many times we told all the vendors we were looking for raw speed."
Given the paucity of SSD vendors, it didn't take the financial firm long to narrow the field down to Xiotech Corp. and its Magnitude 3D 3000 SAN, which retails for $84,000, and the TagmaStore AMS1000 from Hitachi Data Systems. The HDS system was loaded up with read/write cache -- what the engineer calls "their claim to fame," but in the bakeoff with the Magnitude 3D 3000, the broadband-type cache wasn't fine-tunable enough to interoperate precisely with the application.
For its part, the Magnitude 3D 3000 gained a significant advantage based on a simple capability. "With the Xiotech SAN, we could basically take these solid-state disks, mount them as virtual memory sticks and refer to them via a drive letter. We could then dedicate the solid-state disks to our application just like you would with any other resource," he explains.
It didn't hurt that the Magnitude 3D 3000 provided 10 times the performance of its predecessor as it crunched away at tables of massive text files, making queries against them and extrapolating the results against the financial firm's proprietary requirements.
The firm currently has 4TB of raw data and 2TB of usable data in the SAN, and although there is a total of five servers dedicated to it, only the Xiotech machine is working directly with the stock tables application. The engineer defines raw data as the amount of physical space available before any RAID parity, and usable space as the amount of space after all RAID configuration has taken place.
Initial implementation last fall took only about six hours, and since then the Magnitude 3D 3000 has been rock-solid reliable.
"It's been running like clockwork; it's up seven by 24 by 365 and we haven't had to do anything," the engineer says. "Reliability was key for this application because of the nature of the data we've been pulling, and we've had zero downtime."
A 400% performance increase
IC Source Inc. is an information clearinghouse for electronic components. The company with just 12 employees maintains two SQL Server databases that serve its component vendors who list their inventories off the site as well as the customers who buy those components. According to IC Source President Pete Moran, one database contains 79 line items and gets around 100,000 searches a day. Calling that "no big deal," he lauds the other database, which is used to import an average of 15-20 million inventory line item changes each day. Keeping up with that demand is what sent him into the SSD market.
Moran had been dabbling off and on in the flash memory market for several years, during which time he made occasional phone calls to CMOS-RAM SSD maker Texas Memory Systems Inc. However, as he explains it, "They kept coming back with these really expensive, tiny disk space drives" that topped off at 64GB, while his database was around 72GB.
The last time he made his yearly call to the vendor, it said it had introduced the RamSan 400, which the company claimed would hold 128GB, which was more than other, more expensive SSDs offered. Moran promptly lined up a 30-day demo and was so impressed by the results that he bought one of the $140,000 devices immediately. He had it delivered and, along with one other non-IT person, got it up and running within 20 minutes. He needed some additional help connecting the RamSan to a second database and IC Source's new Qlogic Fibre Channel Switch, which took about two hours, so the total install time was two hours and 20 minutes. Moran says he was extremely pleased that a product he thought would be extremely complex and difficult to work with turned out to be so user-friendly.
"There was really nothing to setting it up and configuring it. It was super easy to do," Moran says. "It didn't require any real technical support -- probably an hour on the phone with them."
The big payoff, however, was in the performance and reliability. Moran says the RamSan has provided a 400% performance increase over his old Hewlett-Packard array on smaller files and even more than that on larger ones. For example, inventories that used to take an entire weekend to post now run in 45 seconds. Moran says there hasn't been a single glitch with the system since it was installed, and even if there was, the RamSan is protected by supplemental hard drives and a powerful backup battery that lasts for two weeks.
Moran sums it up by saying, "Since we've had the RamSan, the site has been a lightning bolt."