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InformationWeek on NEC HYDRAstor

Howard Marks recently posted an interesting article about NEC’s HYDRAstor over on his blog at InformationWeek. He discusses the product and how the device is targeted at backup and archiving applications. He makes some interesting points and mentions SEPATON. I wanted to respond to some of the points he raised.

…[the system starts with] a 1-accelerator node – 2-storage node system at $180,000…

Wow, this is an expensive proposition. Comparing this to the list price of a SEPATON S2100-ES2, you could get 2x the storage and 2x the performance for about the same price. Alternatively, you could purchase a configuration with equivalent capacity and performance for about 50% less.

….[the largest system is] a 110-TB 16.5-GB* [sic] behemoth that is like Commodore Vanderbilt’s yacht — “if you have to ask how much it costs you can’t afford it….

* This must be a typo. I believe that the author is actually saying 16.5 GB/hr which matches NEC’s website.

He is right that the cost would be prohibitive for a solution of this size. At a minimum the solution requires 55 accelerator nodes (15,600/300) which results in a list price of $2.75 million, but of course storage is required as well. If we assume one storage node per accelerator, the price jumps to $6.6 million. Now I understand his Vanderbilt quip, but their prices are way out of the industry norm.

Finally, creating a system to validate that information is cost prohibitive. Have they purchased 55 accelerator nodes and 55 storage nodes and validated this performance and configuration? My guess is not. SEPATON’s architecture is designed to support 32 nodes (19,200 MB/sec performance, faster than HYDRAstor), but we do not promote that configuration since we have not qualified it yet. I guess if we wanted to be equally as aggressive, we could claim that performance, but instead we decided to be more conservative and stay with 16 nodes (9,600 MB/sec).

A Hydrastor grid’s accelerator nodes manage the cluster’s file system, allowing backup and archiving applications access via a CIFS or NFS / NAS like interface

NFS/CIFS are well established and widely used in the storage industry; however, in the data protection space, NFS/CIFS is primarily used only in small implementations. VTL is the common interface in large environments due to its simplicity to implement and mature support in backup applications. I am not saying that a massively scalable filer is a bad thing, but rather that data protection is not an ideal market for the technology.

The new accelerator nodes are available with two 10-Gb Ethernet ports eliminating the 1-Gb Ethernet (GigE) bottleneck that’s held NAS backup appliances behind VTLs in backup performance.

A HYDRAstor accelerator has two x 10 Gb Ethernet ports which equates to about 2000 MB/sec, and yet they can only achieve 300 MB/sec throughput? Additionally, in order for the customer to even see that, they will need to implement costly 10 GigE. This makes for tough economics because you not only have to purchase the system but also a new network infrastructure. SEPATON achieves better performance, 600 MB/sec per node, with a substantially cheaper interconnect, 4 Gb FC. (2 front end and 2 back end ports per node, up to 16 nodes).

In the second point, the author indicates that GigE has limited NAS performance. It certainly is true that one GigE port is much slower than 2 Gb or 4 Gb Fibre Channel, but many vendors have solved this by adding multiple GigE ports to their platforms. The other issue is that CIFS/NFS requires more computing overhead on the backup server which results in slower single stream performance. For example, let’s say you have a very powerful 4 TB Oracle server that you are backing up to a 300 MB/sec CIFS/NFS and a 300 MB/sec VTL. Fibre Channel is a much more efficient protocol which means that the backup will run close to the 300 MB/sec. In contrast, the NFS/CIFS backup will run at a fraction of this speed due to the overhead in the system and this bottleneck cannot be resolved by simply adding a faster Ethernet pipe.

In summary, HYDRAstor certainly has interesting technology. The reality of today’s environment is that business value and ROI are key. Certainly, NEC can promote a bleeding edge grid solution, but it comes down to the ROI for customers and in that area, SEPATON has an advantage versus HYDRAstor.

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