While early-edition blades were said to cause significant heat issues, the new versions are architected with superior cooling technology and monitoring to avoid this pitfall. The latest blades also include multicore processors and the same amount of memory, network interface cards (NICs) and host bus adapters (HBAs) as rackmount servers, said Barb Goldworm, the president and chief analyst of Focus Consulting in Boulder, Colo., and author of the book Blade Servers and Virtualization .
Goldworm, who has observed the market from the get-go, said that blade servers have now evolved such that they demonstrate superiority over many rackmount models.
"When blades first came out, they had power and cooling issues, which have been corrected to the point that if you compare blades to rack servers, they are more efficient and are cooler, because the cooling within the chassis has become more efficient," Goldworm said. "The early design also didn't have the horsepower -- CPU, memory, NIC cards or HBAs -- for virtualization. All of these things have been increased."
This year, for example, Dell introduced a new blade server, the PowerEdge M-Series, that impressed analysts who hadn't been keen on Dell's previous blade offerings. This year, Sun Microsystems Inc., Hewlett-Packard Co., IBM Corp. and Verari Systems have also introduced blade servers with high-density memory, dual- and quad-core processors that can run hefty applications and virtualization, without setting the data center on fire.
Sure, a chassis of blade servers will be hotter than a rack of servers, but only because more blades are packed into a smaller footprint than with a rack servers, Goldworm said.
"When comparing blade servers to rack servers one to one, blades are more efficient," Goldworm said. "Blades will help you if you have limited power and cooling capacity in the data center."Blade server users boast improvements
Emeryville, Calif.-based Gracenote, a data provider for Apple iTunes and many other PC applications, has three production data centers throughout the U.S. that handle between 60 million and 80 million data queries each day. The company's servers have to be available every moment every day of the year and to deliver data for applications like iTunes within about 15 milliseconds, said Matthew Leeds, the vice president of IT operations at Gracenote.
Previously, Gracenote used Dell's 1U 1650 and 1850 servers running Solaris as the primary OS, but about two years ago, it upgraded to Sun Microsystems blade servers for its cellular and audio recognition technologies and core databases, Leeds said.
Gracenote replaced 30 racks of Dell rackmount servers with Sun Blade 8000p and Sun Blade x8420 servers. It uses AMD Opteron processors in all its blades, and up to 1 GB of memory per core, Leeds said.
In terms of power efficiencies, Leeds found that the blades consume less power than an equivalent stack of their 1U servers, so cooling costs are lower. Gracenote also cut its capital expenditures and operating expenses by about 25% by upgrading to the Sun blades, Leeds said.
Another company that has reaped the benefits of blade servers is San Francisco-based TechSoup, a nonprofit that provides technology resources to other nonprofits.
Earlier this year, Timothy Suttle, the director of IS infrastructure at TechSoup, switched from aging Dell rackmount servers to blade servers and virtualization to outfit a new data center.
"We needed to refresh our hardware and wanted to improve and be prepared for growth. So, we decided that combining blade servers, SAN [storage area network] and virtualization would be the key for providing room for growth, and to simplify management and reduce our footprint; to create a greener data center," Suttle said.
TechSoup chose iSCSI for its SAN and VMware Inc. offerings for virtualization. With that in mind, the company needed a blade server with several NICs, Suttle said. "Many vendors only offer five NICs, and we needed at least six NICs per server with the SAN iSCSI and virtualization," he said.
In February, TechSoup installed two HP c3000 BladeSystem chassis -- dubbed "Shorty" by HP -- each with six NICs. The medium-sized company uses one chassis of five blades in its staging and development environment and another in its production environment.
TechSoup also runs mission-critical applications, including large databases, and the company's website on VMs hosted on Intel quad-core processor-based blades.
"We have about four or five virtual machines on each physical server in the production environment, and 10 VMs per blade [in testing and development] with VMware," Suttle said.
The business expects to see a huge power savings of about 72% from using more efficient blades and virtualization. To boot, the servers are simpler to manage, so the company will save on operational costs, Suttle said.
"The management of the c3000 is amazing; we have all of the remote management we could want or need, proactive monitoring of the blade components, and it is adaptive. I can adapt fan speeds our shut some off depending on the heat in the chassis, so we can continue to save power down the road," Suttle said. "We've certainly reduced our sys admin overhead. As a growing organization, [the management tools] save us a lot of time. Now that we have them in place, I can't imagine building a server room or data center any other way."Blades gaining in x86 server market
For the first quarter of 2008, Framingham, Mass.-based research firm IDC reported that the server blade market accelerated, with factory revenue growing 53.7% year over year, the fastest growth rate in 10 quarters. Overall, blade servers, including x86, EPIC and RISC blades, accounted for $1.2 billion in the first quarter, or 9.2% of the server market revenue that quarter.
HP had the top spot in the blade market, with 46.9% market share, and IBM took the second spot with 30% share.
As vendors have expanded their products to include small and medium-sized businesses and higher-end workloads through non-x86 architectures, blade server adoption has increased, reported Jed Scaramella, a senior research analyst for enterprise platforms at IDC. EPIC and RISC-based blades accounted for more than 5% of blade revenue in the first quarter of 2008, which is double the share from the same time last year, IDC reported.
Users considering blade servers should make power and cooling efficiency comparisons, Goldworm said. Also, some blade servers have I/O virtualization technology built in , such as HP's c-class blades with Virtual Connect, Dell's M-series with FlexAddress, and Egenera blades with Processing Area Network (PAN) Manager.
"Anything you get on a rack you can now get on a blade," Goldworm said.