IBM turns server sideways for Web 2.0 build-out

by James Niccolai

April 23, 2008 —

IBM has designed a new type
of rack-mount server specifically for companies running heavily trafficked "Web
2.0" sites such as Facebook
and MySpace, the company
announced Wednesday.

Called the iDataPlex, the server is designed to compete with the unbranded
"white-box" PCs that online companies link together by the thousand
to run busy Web sites. IBM said its new server, which runs Linux and is based
on Intel's quad-core Xeon processors, consumes 40 percent less power and packs
more computing punch than a typical rack-mount system. The energy savings come
largely from a new design that requires less power for cooling, IBM said.

Rack servers are the slender machines shaped like an oblong pizza box and stacked
on top of each other in server chassis. The servers come in standard heights
-- 1u or 2u -- but their depth, or how far back they reach into the chassis,
has been expanding as vendors try to cram more hardware components inside.

That has created a problem, according to IBM. Cooling systems blow air over
the servers from back to front, and as the servers become deeper it takes more
energy to power the fans that cool them. "The power used by the fan is
proportional to the cube of the fan speed, so if you want to double the fan
speed you have to use eight times the power," said Gregg McKnight, CTO
of IBM's modular systems group.

IBM's answer is to rotate the server horizontally through 90 degrees, producing
a server that is wider than usual but only 15 inches deep, compared to about
25 inches for a typical rack server. "That allowed us to run fans at a
much lower velocity, and therefore save about 67 percent on the fan energy alone,"
he said.

IBM also pushed two racks together, creating a single wide rack that holds
84 iDataPlex servers. That allowed it to share three power whips between the
servers, while two separate racks would normally use four. Power whips, the
moveable outlets attached to power cables, cost $1,500 to $2,000 per month to
maintain, McKnight said.

The broad surface area at the back also allowed IBM to design an optional water-cooled
rear-door heat exchanger, which IBM said extracts all of the heat from the system,
so it doesn't contribute to datacenter warming.

The trade-off for sharing power cables is a less fault-tolerant system, but
the software used to run busy Web sites is usually designed to fail over quickly
to another server. "We interviewed Web 2.0 companies and they told us unanimously
that they are designing their applications to tolerate server failures. So because
it's more economical and more energy efficient, it's an attractive trade-off
for them," McKnight said.

Joe Clabby, president of Clabby
Analytics, in Yarmouth, Maine, said that philosophy marks a significant
change. The big server vendors have focussed on designing costly machines with
high levels of redundancy, which is what companies need to run back-office business
applications where every transaction is critical.

"In the Web 2.0 world, you don't need that," Clabby said. "If
an IP address drops out, they just kill the server and move to another one.
They're not focussed on business resiliency here, they're focussed on fast,
cheap and fix-it-on-the-fly. That's a big change for IBM and the server industry."

The iDataPlex will compete with homegrown clusters built from standard x86
servers, and with servers from Verari
Systems and Rackable
Systems, Clabby said. "They already make these cheap, turnkey, 'plug
em in and let em rip' servers for Web 2.0 companies. They proved the concept,
now the 500 pound gorilla has landed on their doorstep."

While the main target is Web 2.0 companies, IBM said the servers are also good
for complex financial analysis, video rendering and high-performance computing.
The servers are configured for customers on site at a factory in China, and
are available only to companies that place large orders. Most early customers
are ordering thousands of racks, McKnight said.

IBM wouldn't provide pricing or specific configurations. It said customers
can choose from 22 configurations, with a menu of networking, switch and storage
options. The options include gear from IBM partners such as Avocent,
QLogic and
Blade Network Technologies,
which designed a switch for the iDataPlex, IBM said.

IBM began designing the systems 18 months ago when it realized it didn't have
a product for the burgeoning Web 2.0 market, McKnight said. He is due to give
a presentation
about the systems Wednesday at the Web
2.0 Expo in San Francisco.

IDG News Service