Alacritech, HP boost NAS performance

By Lisa Coleman

A testing lab recently proved a significant increase in network-attached storage (NAS) performance using Alacritech's "integrated storage network interface card"

(IS-NIC)—a derivative of the TCP/IP offload engine—and an unreleased Microsoft Windows .NET operating system paired with Hewlett-Packard's StorageWorks E7000 NAS device.

Compaq, now HP, commissioned eTesting Labs to test its next-generation configuration to confirm that high performance can be achieved with industry-standard products such as the E7000 NAS system, which is also a SAN-NAS bridge based on Windows.

Alacritech's 1000x1 single-port Gigabit Ethernet Server and Storage Accelerator Card offloads TCP/IP processing, as well as iSCSI protocol processing, from the host processor. In turn, the system processor is freed up for application processing while boosting network performance and increasing maximum system throughput.

The E7000 is available now, but it will be re-released with Windows .NET support when Microsoft makes the product available. Microsoft anticipates a .NET server release later this year but could not confirm a specific release date. The Alacritech card is available now for $999.

Today, users can boost performance by as much as 40% by coupling an E7000 with the Alacritech card, according to HP officials.

"At best, any NAS appliance spends half its time doing software protocol processing for the network," says Joe Gervais, Alacritech's director of product marketing, "and the other half of the time is spent doing all the metadata management for talking to the storage. We're taking the network element that's consuming all those resources and giving all those resources back to the NAS appliance for file system management."

The test configurations included the E7000 NAS appliance with two Emulex host bus adapters (HBAs) connected to a Compaq MA8000 SAN equipped with six HP StorageWorks 4314R storage cabinets. Each cabinet contained 14 36GB drives for a total of 3TB. The NAS system included two Alacritech cards.

The E7000 is traditional NAS-type storage. The NAS head currently only connects to HP's disk arrays but will work with non-HP SANs in the near future.

The lab used the NetBench 7.0.2 benchmark tool—which measures how well a file server handles I/O requests from 32-bit Windows clients—to test a single-node NAS configuration. Test results showed an average peak throughput of 1,392.599Mbps for the RAID 0 configuration, and 1,378.014Mbps for a RAID 5 configuration. A clustered NAS configuration with a RAID 0 disk array produced an average peak throughput of 2,620.940Mbps.

Using the Iometer benchmark—which is an I/O workload generator and performance analysis tool—the single-node test system scored 1,683.544Mbps with 2,6936.74 I/Os per second using 8KB transfers. With 64KB transfer request sizes, the system achieved an average peak throughput of 2,045.016Mbps with 4,090.026 I/Os per second.

Based on these results, Mark Nagaitis, director of HP's NAS division, claims that the next-generation E7000 with the Alacritech card and Microsoft's .NET will be faster than BlueArc's Si7500 storage system and Network Appliance's NAS devices—at a lower cost of ownership.

BlueArc's CTO Geoff Barrall disputes the claims of higher performance and lower cost of ownership. "Although it's commodity equipment, the Compaq test configuration was [priced] significantly higher than a BlueArc system," says Barrall. "To suggest that using commodity equipment is cheaper certainly isn't true for that particular configuration."

Last June, BlueArc commissioned a similar benchmark test for its Si7500, but to compare the test results would not be an "apples-to-apples" comparison, according to Barrall. While BlueArc's maximum throughput figures were a bit less than HP's, Barrall argues that BlueArc's figures were skewed due to older CPUs and a 100Mbps Ethernet connection, compared to HP's test that was run on faster CPUs and a Gigabit Ethernet network. Barrall also claims that BlueArc's devices offer better scalability.

BlueArc's next-generation storage system will hit the streets later this year, and the company may commission further benchmark tests, according to Barrall.

Network Appliance panned the NetBench and Iometer benchmarks since they are not "realistic" configurations, according to Keith Brown, Network Appliance's director of technology and strategy. Brown believes the benchmarks were engineered to disregard disks and concentrate on RAM. However, he says that the benchmarks do prove that Alacritech's card works.

"It's a good benchmark for Alacritech because it shows that their board has decent throughput. [But the benchmark's] got nothing to do with what happens to data once it's been brought into the storage system by the card," Brown adds.

Network Appliance uses the Unix-based Spec SFS benchmark for testing its devices. Brown believes that Spec SFS more accurately exercises disk subsystems and measures throughput and response times.

This article was originally published on June 01, 2002