In part 1 of this feature we looked at BlueArc and Exanet. Now we discuss Isilon and Montilio. On June 5th we will inspect NeoPath, StorageX (Brocade's NuView) and OnStor.

Isilon provides clustered NAS storage. It has recently and very publicly been chosen by MySpace, possibly the fastest-growing website on the planet, to hold some of its data because nothing else could scale or perform as well for MySpace, 20TB so far.

Isilon's IQ product scales up to a theoretical 528TB of capacity and 7 GB/sec of performance in a single file system and shared pool of storage. There are various Isilon products; the IQ1920i scales to an 80TB cluster; the IQ3000i to a 126TB one; and the IQ6000i to a 250TB one. The software is called OneFS and combines a file system, a volume manager and RAID into one piece of storage system software with files and file metadata striped across all nodes.

Access protocols supported are traditional NAS NFS and CIFS plus FTP and HTTP, making it suitable for web access.

The hardware nodes are clustered with InfiniBand or gigabit Ethernet and high-availability is built-in. There is N+2 protection against multiple drive or node failure. Isilon says it has the industry's fastest drive rebuild time with a 250GB drive being rebuilt in a hour or so.

There are no SPECsfs figures for Isilon. It emphasises overall throughput and says it can deliver over 6,000MB/sec from a single OneFS file system. A NetApp FAS 980 can deliver about 500MB/sec and an EMC Celerra 7046 around 400.

There are over 70 Isilon customers, many being high-end blue chip ones. Exanet's Schwartz says: "We do see (Isilon) a lot, mainly in media and post-production houses, not in real-time. They're typically low-to-medium size systems by capacity, 30TB probably. Isilon doesn't have a single cluster node that supports more than 30TB. Its (product) is very good for post-production needs but not so good for large capacity needs."

We mentioned Montilio for the first time a couple of weeks ago. It was because the addition of its RapidFile storage to LAN gateway card to a NAS server made it really streak along. The SPECsfs results noted were:-

- Montilio 47,586 ops
- EMC Celerra NS700 - 36,335 ops
- NetApp FAS980 - 36,063 ops.

Montilio claims that RapidFile offers three to six times the performance of current alternatives at 15 to 25 percent the price, which is $2,899. The card is added to a NAS product, or file server, and accelerates NAS traffic away from the box. It includes twp gigabit Ethernet ports with TCP/IP offload engines (TOEs). There are also two 2Gbit/s Fibre Channel ports for linking to storage arrays. The card separates the data and the control paths for the data. The speed up is greater for large block sizes and smaller for small block sizes.

Montilio CEO Michael Tsuk pointed out: "This contradicts the great SPEC numbers we get since SPEC is very small packets (and control data) intensive. We knew we are good at throughput so the SPEC numbers were a very good surprise for us as well."

Data is moved directly from storage to the output port bypassing the servers own memory and processing. That is used solely for control processing. The host server handles control and maintenance jobs; the RapidFile card acts as a data transmission (NFS/CIFS) offload engine and a TOE.

The RapidFile product includes a module that runs in the host server O/S and gets file mapping information from it for use by the RapidFile card. Thus it needs good integration with the NAS server O/S. So far this has to be either Red Hat or SuSE Linux.

Windows and other Unix support is being added. So are SCSI and iSCSI protocols. That suggests the card could be an IP SAN accelerator too.

Consider this card as an I/O performance accelerator for individual NAS products. It is a point product in that sense. It does not include a global namespace facility and thus doesn't apply to clusters of NAS products. Nor can it virtualise NAS resources. It can't turn a pedestrian NAS product into a BlueArc-class performer. It can turn a NAS crock into a halfway decent box though and a halfway decent box into a good one.

Michael Tsuk adds: "It will turn a simple server into a faster than FAS980 machine. But, it will not add the global namespace and other bells and whistles. These come from the software the NAS or the file server has. RapidFile is a 'lower layer' type of product. Also, it does not prevent working in a clustered set-up, just that this comes from another vendor."

If you have one or several NAS boxes that don't perform fast enough but have enough capacity and/or capacity growth potential then the Montilio product looks a good initial fit.

EMC and NetApp and HP and Sun?
The NAS performance and scalability and virtualisation and clustering stakes are being driven by these companies, plus Acopia, and not by EMC, HP, IBM or NetApp. With the growth rates being reported by them there is clearly a booming market for higher-performance, higher-capacity NAS systems, ones that face constantly growing needs for more performance and more capacity.

One way to do it is to cluster NAS gateways together to add performance and capacity, as Exanet and Isilon do. Another way is to build dedicated hardware and software to accelerate NAS performance and provide high capacity; the Acopia and BlueArc route.

We are waiting for what must be the inevitable entry of EMC (via Rainfinity technology), NetApp (via Spinnaker technology) and Sun (AMD/Solaris-based Thumper project?) into this market. IBM may OEM the NetApp product when it arrives. HP's route to market is unpredictable by this writer at the moment. But the big five storage and sever/storage vendors surely must enter the high-end NAS market. It is becoming too big to ignore and they all have NASty (excuse the pun) holes in their product lines right now.

Part 3 of this super-NAS feature will be posted on June 5th and look at NeoPath, NuView (Brocade's StorageX) and OnStor.