Escalading RAID Options
Escalade 9500S-12MI SATA RAID Controller: High-performance RAID controller that uses SATA drives
The Escalade 9500S-12MI is the latest in a series of RAID controllers from 3Ware, which Applied Micro Circuits (AMCC) acquired last year. The Escalade 9500S-12 uses commodity hard drives rather than SCSI drives to achieve fault-tolerant, high-performance drive arrays less expensively. For many applications, the SATA controller provides performance similar to SCSI at about one-twelfth the price of Ultra320 SCSI drives and controllers.
We tested a dual-processor 3 GHz Xeon system with 1 GB RAM and eight Maxtor 7Y250M0 MaXLine Plus II 233 GB SATA drives. RAID 5 capacity totaled 1.59 TB, and the eight-drive RAID 5 array processed just over 400 MB per second sequential reads and more than 100 MB per second sequential writes using IOMeter.
The 9500S series supports up to 3 TB per controller and offers a number of new features that compare favorably with SCSI controllers, including:
Using a mix of reads and writes intended to be representative of normal server use, the Escalade 9500S achieved an average of 90 MB per second of sustained throughput. While I/Os per second are not in the class of Ultra320 SCSI at a peak of 192 I/Os per second, this is only an issue with some older databases incapable of queuing requests. These numbers were achieved with a server utilization slightly less than 3 percent, and they required some manual tuning of parameters using the registry editor in Windows 2003.
This level of performance should be adequate for pretty much any application, short of a full-on enterprise database. And even at that level, most administrators will be more concerned with the theoretically higher mean time between failure of enterprise-caliber drives vs. untested SATA drives with 24x7 duty cycles, rather than a set number of I/Os per second.
Note that the "MI" in the full model number designates the multilane internal connector that consolidates four separate SATA drive connectors into a single connection on the board. This simplifies the internal cabling scheme considerably. The 9500S is also easier to manage than previous versions: It has a Web-based management utility that makes remotely managing the controller and RAID array a simple task.
The 9500S series supports up to 3 TB per controller and offers a number of new features that compare favorably with SCSI controllers, including 128 MB of ECC cache (upgradeable to 1 GB), variable stripe size for performance tuning, backup of firmware for recovery after failed upgrades, staggered drive spin-up to reduce power requirements on startup, support for battery backup of cache, and e-mail notification of alerts via the management utility.
The controller can use RAID 0, 1, 10, 5, or 50, although we suspect most organizations will set up RAID 5. For users that require more than 3 TB, up to four controllers per system are supported.
We had one minor issue with the 9500S. Unlike a SCSI RAID controller, the array attached to a 9500S is not bootable without drivers. If you want to boot Windows or Linux from the array, the 3Ware driver must be added during installation. If you have a separate boot drive, this is not an issue.
In all, the 9500S is an extremely capable low-cost controller that rivals its SCSI competitors in most applications and supports the much less expensive SATA drive specification. Considering that several 400 GB SATA drives are priced lower than one 180-GB Ultra320 SCSI drive, finding a reason to stick with the less-compelling SCSI is difficult.
Vendor Home Page: 3Ware
Product Home Pages: Escalade 9500S-12MI
Size: 1.59 TB
Supported Driver Operating Systems: Windows, Red Hat Linux, SUSE Linux, and BSD
Price: 3Ware 9500S-4LP Serial ATA 150 RAID Controller Card, $399
3Ware 9500S-8 Serial ATA 150 RAID Controller Card, $599
3Ware 9500S-12 Serial ATA 150 RAID Controller Card, $899
Overall Rating: 5
Pros: Very high performance, even relative to SCSI; Low cost per gigabyte; Supports SATA 100, 133, and 150 drives.
Cons: No NetWare support; Array not bootable without drivers.
Article courtesy of Server Watch