eSATA External Storage Drive Reviewed
Tom's Hardware has a practical look at an eSATA drive offering from Taiwanese storage firm Thecus. From the article: "Thecus' N2050 is one of the first external twin-drive RAID boxes that uses eSATA. As expected, its performance was far better than what USB 2.0 offers. The end result is impressive. The date transfer rate of 30 MB/s that USB 2.0 offers does indeed pale in comparison to 100 MB/s for eSATA, while the WD1500 drives are capable of delivering even better performance in RAID 0. It is also good to see that Thecus did not throw the USB 2.0 interface away, because it is a nice backup interface whenyou want to use the device with other computers via USB 2.0."
Also, mentioned in the article... the SATA bus boasts a wonderful 3Gb/s (or 300MB/s). This however, is not the bottle neck when it comes to performence. As the article mentions, the top SATA drives on the market today only get about 85MB/s read/write to the disk. So although you may get 300MB/s from the disk cache, and the controller, you'll never really get 300MB/s. Still, it's miles from Ultra-ATA.
The upcoming (high def) TiVo Series 3 has an e-SATA port. Adding more recording space will be a whole lot easier than it was before, especially for the less adventurous folks.
It is true that a single drive cannot saturate the SATA channel. (85MB/s is actually a _very_ generous estimate. Typical performance is closer to 50-60MB/s). So, SATA certainly doesn't need more bandwidth in the near future. However, for eSATA, the extra bandwidth is _very_ useful. It would allow manufacturers to produce RAIDs with eSATA ports instead of SCSI or FC. (Right now, you still need a SCSI or FC card if you want to get any sort of performance). This would effectively commoditise the low-end RAID market, which is a very welcome development.
___
If you think big enough, you'll never have to do it.