BlueArc guns for EMC, NetApp


BlueArc, a Mountain View, CA-based start-up, is setting its sights on becoming a leader in the fast-paced network-attached storage (NAS) market. With a unique architecture that promises to eliminate server I/O bottlenecks, the company hopes to challenge NAS market leaders Network Appliance and EMC.

"Within three years, we ought to be the only company that will be able to challenge EMC and NetApp on their turf," says Enrico Pesatori, CEO of BlueArc. (Before joining BlueArc, Pesatori was a senior executive at Compaq and former president of Tandem Computers.)

BlueArc's Si7500 SiliconServer, which will ship in late April or early May, offers 2Gbps throughput and up to 200TB of capacity per server. The main difference between BlueArc's technology and other NAS architectures is that much of the technology is based in hardware instead of software.

Geoff Barrall, company founder and chief technology officer, designed the new architecture to overcome the server bottleneck in high-speed networks. Traditional server technology has been designed for computational speed and not for throughput speed, he claims, and today's servers cannot match the throughput performance of Gigabit Ethernet and Fibre Channel interconnects. Even as processors have been designed with more speed, server architectures have not kept pace.

BlueArc developed hardware implementations of traditional software functions in its SiliconServer architecture, which offers 2Gbps throughput.
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According to Barrall, traditional server architecture's primary bottleneck has been the bridge enabling communication between the memory and other devices. Only one device can talk to the memory at a time. All the data traveling through the server flows through the memory as well. Therefore, data can be handled only by one device at a time. "This is awful if you are trying to get data from the storage to the users," says Barrall.

Many companies have added Gigabit Ethernet and Fibre Channel to their networks to help speed up server environments. However, the upgrades provided small changes in overall performance because the servers cannot cope with the data load, according to Barrall. BlueArc developed its server to handle the data load and perform 2Gbps data transfers from storage to users. "We're realizing the promise of Gigabit Ethernet and Fibre Channel," says Barrall.

The SiliconServer has a hybrid architecture with a NAS front-end and a Fibre Channel storage area network (SAN) back-end that enables scalability to 200TB. (The architecture has a physical limit of 2 petabytes.) There are two separate data paths for storage (see diagram). Each path can clock 1Gbps, and the server can read and write data at 1Gbps in either direction.

Traditional servers perform data transfer via software that reads the data from the storage interface and puts it into memory. More software pushes the data through the network to users. "In our box, it's all done in hardware," explains Barrall. "If you want to move data at gigabit rates, you have to do it in hardware and not in software."

BlueArc developed chipsets to perform traditional software functions. The company has taken the software from the TCP/IP stack and implemented it in hardware with re-programmable gate arrays (RGAs) and attached memory. A protocol subsystem, file system, and storage subsystem are all implemented in hardware as well. The file system is a central unit that works with Unix and Windows, allowing file sharing from the two environments. The storage subsystem has a full implementation of a Fibre Channel host bus adapter, says Barrall. In addition, the server's storage scales inside its internal SAN, where RAID controllers with attached storage can be added.

BlueArc officials claim that the server can support tens of thousands of users. Pricing will be released next month.

This article was originally published on March 01, 2001