Advanced Computing in the Age of AI | Saturday, July 13, 2024

Servergy Pits Power-Linux Servers Against ARM, X86 

Not everyone thinks that ARM processors will be the only viable alternative to X86 processors in the datacenter when it comes to energy-efficient computing. Servergy, which just uncloaked from startup mode with its first machine, is putting its money on the Power architecture. And it is doing so because big customers are asking for Power-based servers that are tuned more for distributed workloads than are IBM's own very brawny Power Systems machines.

"We are literally being pulled into this market by customers," says Bill Mapp, founder and CEO of Servergy. The company is based in McKinney, Texas and has been hinting about its plans to put Linux-based machines based on Power processors into the field for the past year.

Mapp can't name names, of course, because that is often the way with large enterprises who want to be careful not to be officially endorsing products, but he tells EnterpriseTech that one of the top stock exchanges in the world has approached Servergy to do custom designs of Power-based servers.

The first machine out of the door from Servergy is the Cleantech CTS-1000, and it is based on an eight-core Power chip, but not IBM's own Power7 or Power7+ processors. Servergy has chosen Freescale Semiconductor's QorIQ P4080 as the motor for its machine, which burns a lot less electricity than IBM's own Power7 and Power7+ chips. The QorIQ P4080 also has a lot less oomph for single-threaded work, runs at a much lower clock speed, and does not have NUMA multi-socket scalability, and Mapp is perfectly happy to admit to all of this.

"IBM's Power chips are ideally positioned for heavy workloads that are compute intensive," says Mapp. "We are aiming at the verticals that have I/O contention, such as Web caching and distributed big data applications, such as those used in financial services, telecommunications, and clouds. There is a lot of pent-up demand for Power in the datacenter."

The CTS-1000 has a footprint that is about the size of a legal pad, and is a standard rack unit (1.75 inches) high. You can put two of them side-by-side in a shallow telecom rack, or you can put four of them in the pizza box enclosure that is standard for 1U rack-mounted servers. Starting in December, the company will ship a preconfigured setup called the HyperRack that will cram 152 of the CTS-100 nodes into a single rack, which will yield 1,216 cores in a single rack.

The QorIQ P4080 is based on Freescale's 32-bit e500mc core, which has 36-bit memory addressing so it is not locked into a 2 GB memory footprint like other 32-bit processors that do not have such memory extensions. The P4080 chip was designed for networking gear, for both the control and data planes in switches, routers, and other kinds of equipment that play further up in the networking stack.

The P4080 has eight cores running at 1.5 GHz, it is etched using 45 nanometer processes; and with all of its caches and coprocessors it has a thermal design point of 30 watts. Each core has 32 KB of L1 instruction cache and 32 KB of L1 data cache, with a 128 KB L2 cache on top of that. A 2 MB L3 cache is shared across the cores on the die. The chip has two 64-bit memory controllers that can support DDR2 or DDR3 main memory; significantly, the memory controllers have ECC error scrubbing, which is necessary for server workloads. In theory, this chip can address up to 64 GB, but Servergy is topping out at 32 GB.

The Freescale system-on-chip has integrated network controllers that can sport two 10 Gb/sec and eight 1 Gb/sec Ethernet ports. (This is what Mapp was talking about when he said high I/O environments. The CTS-1000 machine is exposing two 10 Gb/sec and two 1 Gb/sec ports to the outside world.) The chip also has three PCI-Express x4 controllers and two serial RapidIO controllers on the die.


The CTS-1000 server has four drive bays, and it supports up to four 2 TB SATA drives or a selection of solid state drives. Servergy is offering a mix of LSI MegaRAID adapters to control the disk or SSD storage in the tiny machine. The entire CTS-1000 server node, loaded up with memory and disks, burns under 130 watts.

IBM's Power7 and Power7+ chips, by contrast, burn anywhere from 130 to 180 watts, depending on the model. Those figures are based on hearsay because IBM does not publish the thermal ratings for its Power processors.

The CTS-1000 system can be loaded up with Linux distributions from Red Hat, SUSE Linux, and Canonical and supports KVM for server virtualization with the promise of others "coming soon."

The CTS-1000 has a pretty steep sticker price, at $15,000 configured with 32 GB of memory and four 2 TB drives. But remember that this is list price, not street price, and that this machine includes the networking features on the QorIQ chip. On an IBM Power system, and on most X86 servers, you have to either put the network interfaces on the motherboard or in a peripheral slot, and these are not cheap.


It is a bit perplexing at first as to why Servergy didn't go with the P5020 QorIQ chips, which have 64-bit e5500 cores. But the P5020 has only two cores running at 2.2 GHz, and has a lot less network bandwidth coming out of the chip (one 10 Gb/sec and four 1 Gb/sec ports) even if it does have two integrated SATA 2.0 ports. The T4240, which has the even newer e6500 cores and offers about 2.5 times the performance per core of the e500mc core used in the P4080 chip, might also make a better server processor. The T4020s burn about half as much juice for the same performance as the Core i7 chips from Intel in the "Sandy Bridge" generation; it is not clear how they stack up to the "Haswell" Core i7 and Xeon E3 chips, but you can bet Intel has closed the gap.

Mapp is not about to divulge his future product plans, but the company is committed to the Power architecture and has no plans to build systems based on ARM, Atom, Xeon, or Opteron processors. "Power is proven and it is years ahead of ARM and Atom in the datacenter," says Mapp. "We are looking at all of the Power options that make sense."

The CTS-1000 servers and HyperRack setups start shipping in the middle of December. They are currently being made by an unnamed contract manufacturer in Texas, and Servergy has alternate manufacturers lined up to scale up as needed. The company is working with distributor Avnet to push its products, too.