3Ware Escalade IDE RAID Controller
Most RAID controllers rely on SCSI devices, primarily because of the lack of speed, reliability and connectivity that IDE/EIDE/ATA drives offered. That’s all changed, as ATA drives are now almost as fast as the fastest SCSI standard, capacity of the drives exceeds most SCSI drives, and costs of ATA drives have dropped. The four-peripheral limit of EIDE/ATA drives has been cleverly worked around, and now a new genre of RAID controllers is available for much less than equivalent SCSI systems. 3Ware’s Escalade 6000 Series ATA RAID controller is one of these new units, and has made an excellent impression in our testing lab.
The Escalade 6000 Series board is a full-length PCI card with eight IDE/ATA connectors on the surface, along with on-board CPUs and cache. The back plane of the board is blank with no connectivity for external devices. The Escalade 6000 Series package includes eight ATA cables, four Y-adapter power cables, and diskettes holding controller software for Windows 98, Windows 2000, Windows NT, SuSe Linux and RedHat Linux, as well as a perfect-bound manual. The Escalade 6000 Series is capable of handling eight ATA drives, each on their own controller cable, in RAID 0 (stripe), 1 (mirror), and 10 (striped mirror) arrangements.
Installing the Escalade 6000 Series is simple: insert the board in an available PCI slot, run cables to the drives, install the controller software, then configure the drive array. The entire process is time-consuming only because of the need to mount the ATA drives and cable them: actually installing the controller card and the software takes a few minutes. The entire controller (regardless of the number of drives attached) requires only a single IRQ from the host system, and can coexist with existing motherboard-based IDE or ATA drives. You don’t have to fully populate the eight drives: you can start with four and add drives one at a time until the maximum eight is reached. Of course, as you add drives you may need to recreate the disk arrays.
We tested the Escalade 6000 Series with eight Quantum Fireball 30GB ATA drives, picked up in bulk from a local distributor to provide an inexpensive 120GB array (240GB total capacity but mirrored, giving only half the total effective capacity). Creating a RAID 10 array took a few minutes, and formatting took more time, but after that the array was fully available. The Windows environments get mice windowed interfaces for the configuration and status routines, while Linux (we installed on both SuSe and RedHat systems) get character-driven interfaces. Still, the menus are useful and well thought out.
Performance will be an important consideration for anyone setting up a disk array. We compared the Escalade 6000 Series with two on-hand SCSI RAID arrays, both from Adaptec. While the effective throughout of the two Adaptec arrays (both using 10K RPM SCSI drives with on-board caching) was slightly faster, the Escalade was very close. In real life, the differences between the two would not be noticeable except in benchmark conditions. We measured a sustained transfer rate of 72MBps for the Escalade 6000 Series and a peak transfer rate in excess of 100MBps (the limit of the measuring software we used). The Adaptec setup had a sustained transfer rate of 83Mbps, which is close enough considering the cost of the Adaptec setup was over three times that of the 3Ware setup. The Escalade 6000 Series uses ATA/66, and would probably perform faster in the newer ATA systems.
The Escalade 6000 Series performed flawlessly in testing, even when subjected to repeated copies of very large video files (ranging from 6GB to 30GB) back and forth from a server. The array worked well when we failed a drive (by removing the power cable), and slowed only a little while rebuilding the missing data from the RAID 10 array. Failing a second and third drive in the eight-drive array slowed the system more, but still provided acceptable performance while the drives were rebuilt.
The Escalade 6000 Series is available in two, four, and eight port models at a variety of prices. For those looking for a RAID controller that costs a fraction of the SCSI equivalents, the 3Ware Escalade 6000 Series is an excellent product to consider.
Summary: A fast, flexible ATA RAID controller that performs as well as SCSI RAID controllers at a fraction of the total system cost.