Montilio's RapidFile PCI-X card relieves network file server congestion.
March 8, 2005 | BioTeam regularly evaluates emerging technology products to find better, cheaper, or more practical tools for handling vexing research computing infrastructure issues. Current and emerging IT products are brought into our lab facilities for two main reasons: to see if they work as advertised, and to determine via hands-on usage if they are something BioTeam would feel comfortable recommending to others. The subject of this column is a storage product that falls into the "clever" or "why didn't I think of that?" category.
BioTeam first became aware of Montilio in early 2004, when the company was in stealth mode and keeping product plans tightly held. Initial talks about the yet-to-exist item were interesting enough that both parties maintained contact until late-beta hardware was available for initial testing in January 2005. By the time this column is published, Montilio will have exited stealth mode with shipping product released for general availability. The hardware made available for our testing is expected to closely match the shipping product.
What is it? Montilio calls it "RapidFile," and it is nothing more than a full-length PCI-X card intended for use in network-attached file servers. Nothing about RapidFile is exceptionally new or revolutionary: Montilio has cleverly combined several existing and well-known technologies with a custom chipset and some driver software. The end result is a PCI card that can turn a cheap single- or dual-CPU server into a network file-serving monster capable of standing toe to toe against much larger and more expensive systems.
CLEVERLY SIMPLE: The RapidFile PCI-X card relieves network file server congestion and boosts performance.
OK, enough teasing and beating around the bush. The RapidFile PCI card combines dual QLogic Fibre Channel storage host bus adaptors (HBAs) with dual Silverback gigabit ethernet network interfaces augmented by TCP offload engines. The Fibre Channel and gigabit ethernet devices integrate seamlessly with the host server system while the Montilio ASIC chip and driver software work to accelerate file-serving operations.
The value in this is pretty compelling for people who need inexpensive yet high-performance NFS from network-attached storage systems. By combining storage controllers and network interfaces on the same PCI card, Montilio is able keep utilization of both the storage and network data paths high without placing a significant load on the file server itself. File operations and data traverse only the PCI card — there is no need to pass traffic up through the system bus to the CPU and operating system. The Montilio ASIC chip and driver software separates data payloads from control commands, and only the control commands are passed along to the host operating system and CPU.
Two immediate advantages seen with RapidFile are the removal of the PCI bus as a potential rate-limiting performance bottleneck and the financial savings realized by using cheaper server configurations than what would normally be required.
A third distinct advantage that BioTeam sees is relative transparency of the hardware and lightweight system requirements. We prefer to let scientific and research needs drive our IT planning, and generally frown upon vendor products that demand rigid system and software configurations in order to function. RapidFile has no requirements or special software for clients at all, and when the card is placed into a Linux server the operating system merely sees additional well-known devices, including the PCI Bridge, the QLogic Fibre Channel HBAs, and the gigabit ethernet interfaces. As for the driver software and daemons that must run on the server, Montilio says its code is straightforward enough that the company can build versions for the common Linux distributions and kernel combinations. Support for Windows-based servers and CIFS file services is forthcoming.
The January 2005 tests were conducted in the labs of Cambridge Computer, a well-known company specializing in complex storage and backup situations. In addition to lab space, Cambridge Computer provided the Fibre Channel switch and IBM storage arrays. BioTeam provided IBM e325 Opteron and Sun V60 Xeon client computers, and Montilio provided the RapidFile card and the file server.
To highlight the ability of RapidFile to run on inexpensive hardware, the file server machine had only a single 2.8GHz Xeon CPU and 2 GB of physical memory, and was running RedHat 9 as an operating system. In one of our simple tests, we were able to observe the file server reporting a utilization level of less than 5 percent while our client nodes were nearly saturating the gigabit ethernet links with long NFS read and write requests.
So is BioTeam recommending RapidFile? The short answer is "not quite yet," as we need to re-test with the shipping version of the card as well as deploy it in a larger and more realistic research computing setting. As it stands, RapidFile is certainly interesting enough for us to continue evaluating.
Is this sort of "combo card" packaging merely a niche product or something that actually addresses a current problem, or cost or performance issue? Let me know what you think at firstname.lastname@example.org.