Stress Reduction Redux

Continued from 'Stress Respite; Next Step, Star Trek?'….

I've got my TeraStation set up in RAID 5 mode, for ~480 GBytes of available storage capacity. Other options include single-disk (four 160 GByte partitions), disk spanning (which delivers the maximum 640 MBytes of aggregate storage) and RAID 1. Both the TeraStation and my Gigabit Ethernet switch support Jumbo Frames, but alas none of the computers' NICs do, so I'm not able to harness that bandwidth-boosting option. However, when copying a 6+ GByte file from the Dell to the TeraStation I still measured 60 Mbps peak performance, and limited benchmarking so far with Iometer (a tool which I'm still coming up the learning curve on) suggests that >100 Mbps peak read speeds from the TeraStation are also possible.

Let's focus a bit more closely on that write speed. Take a look at this screenshot I grabbed during the aforementioned 6+ GByte file transfer operation. Notice the periodic lulls? The TeraStation does parity bit calculation and generation (an essential part of the RAID 5 write algorithm) under software control on the PowerPC CPU. I suspect that's what's going on during the pauses between transfers; the TeraStation grabs a bunch of packets, generates and writes both the data and associated parity information, then grabs some more packets….

Although I'm happy with my new toy, my search for the perfect NAS setup continues. Buffalo has provided me with a review sample of its LinkTheater Progressive Scan DVD and High-Definition Wireless Media Player, which works in conjunction with the PCast software built into the TeraStation to stream audio, standard-definition (which it up-scales to pseudo-high-def if necessary) MPEG-1, MPEG-2 and MPEG-4, and standard- and high-definition DivX and Windows Media Video (non-DRM) content over the LAN. If converting HDV to DivX HD or WMV HD works, I might finally have a reasonably user-friendly means of displaying my high-def camcorder's output on my television. Alas, the LinkTheater doesn't currently play 720p MPEG-2 transport streams, but its clone from IO-DATA does, so I remain hopeful.

The folks at Infrant Technologies have also graciously supplied me with a review unit of their ReadyNAS, which is notable for its consumer-friendly X-RAID (link is to a PDF) approach to RAID, its hardware-accelerated parity generation facility, and its support for SATA-150 drives. I hope to give the ReadyNAS X6 a whirl sometime this month; until then, content yourself with the Tom's Networking evaluation of the system, along with the in-depth writeup my colleagues at In-Stat MicroDesign Resources did on its network storage processor (summary here, full report here for Microprocessor Report subscribers).

If this writeup has whet your appetite and you're ready to take the TeraStation plunge, I encourage you to keep a close eye on sites like DealNews and Techbargains. The list price on the 1 TB TeraStation is $1000, but I've seen it online for as low as $750 after rebate. Similarly, the 0.6 TB version sometimes sells for $605 AR online. Brick-and-mortar Fry's Electronics stores frequently have one of the TeraStation versions on sale, too. Happy shopping, and NASsing!