Orthodox server designs are getting a facelift with Intel's Nehalem-EX processor, and server makers are capitalising on new memory features in the chip that boost application performance.
The new chips include changes that provide faster access to memory, and IBM, NEC and Dell have changed designs to take advantage of those features.
Intel has put four memory channels in Nehalem-EX processors to increase memory bandwidth. Servers with Nehalem-EX can also include separate buffered memory chips to temporarily store data alongside the main memory for faster execution.
Beyond the number of cores, system performance depends on a number of factors like on-chip cache and memory, says Jim McGregor, chief technology strategist at research firm In-Stat.
Intel's memory enhancements are an important step forward as the company tries to push the x86 architecture into the high-end server market, which is dominated by IBM's Power, Oracle/Sun's Sparc and Intel's Itanium processors, McGregor says. System vendors have typically tried to distinguish x86 server offerings based on the number of cores and virtualisation, but memory could become a major distinguishing factor for server vendors trying to enter the high-end server market.
"The increased memory capability is huge. It really does open up more applications," McGregor says. Large chunks of information can be moved to the memory quicker for faster processing, he says.
Lack of memory is a major performance inhibitor for many applications in servers, says IBM Fellow Tom Bradicich. If database applications are to be robust and high-speed, large amounts of data need to access the memory very quickly, he says.
"This can result in a large number of disk accesses, and spinning disks are among the slowest components in the server. Memory is among the fastest components in the server, and with extra memory, we can speed up the access," Bradicich says.
Bradicich is one of the architects of IBM's new eX5 server architecture, which decouples memory and processors into separate units. The memory is stored in a 1U drawer that IBM says packs 600 percent more memory. Internal server RAM may not be enough for some applications, and with eX5, IBM is extending the memory capacity of servers, Bradicich says.
The memory drawer is connected to a server by a specially designed chip to reduce latency. IBM has said that the new eX5 servers will run on Nehalem-EX chips. With the new server architecture, users can buy only the memory they need instead of buying servers, Bradicich says.
Dell has introduced patent-pending technology called FlexMemory specifically for Nehalem-EX servers, which can scale the memory capacity without adding new hardware. Dell's new technology is silicon that manages and manipulates the memory in order to double capacity, overcoming limitations that typically throttle the amount of memory that can fit in servers.
Dell late last month introduced two rackmount servers: the PowerEdge R810, which will run on Nehalem-EX chips, and the PowerEdge R815, which will run onAMD's new 12-core Opteron 6100 chips. A two-socket R810 server supports 512GB of memory, which is double that of the R815 server.
NEC is also relying on larger memory capacity as one area to boost performance, says Mike Mitsch, general manager for the IT platform group at NEC Corporation of America. The company recently introduced NEC Express5800/A1080a server, which will run Nehalem-EX chips and include up to eight sockets and up to 2TB of memory capacity.
"Exploiting the four memory channels implemented into the Nehalem-EX was one of the key areas of the architecture," Mitsch says.
"You can increase the amount of memory without sacrificing the speed," he says.