3Ware/AMCC 9000 Series
The 9000 Series from 3Ware/AMCC has now been available for a few months. It differs from its SATA competitors in that it has a hardware XOR unit, plus the attractive StorSwitch architecture. This technology, described by 3Ware as "non-blocking switching," differs from UltraATA and SCSI protocols in that there are point-to-point connections to each drive. Each hard disk can thus be addressed with the maximum possible interface bandwidth. In the case of serial ATA that means at the moment 150 MB/s per device, while the 320 MB/s with UltraSCSI are used shared between all the connected drives.
3Ware controllers have proved to be powerful in the past. With the 9000 Series, the manufacturer clearly intends to throw down the gauntlet to the competition. However, 3Ware's ambitions don't quite come off in terms of the features, because Broadcom has set the bar very high as a result of the Fulcrum architecture acquired from Raidcore. All the same, 3Ware has nothing to be ashamed of, either.
| 3Ware/AMCC 9000 Series | |
|---|---|
| Models | 9500S-4LP (4-channel SATA)9500S-8 (8-channel SATA)9500S-12 (12-channel SATA)8- and 12-channel also as multi-lane versions |
| RAID support | 0, 1, 10, 5, 50, JBODin hardware |
| Interface | 64 Bit PCI-X, 66 MHz |
| Maximum array size | 3 TB |
| Cache memory | 128 MB ECC in the form of an interchangeable SO-DIMM |
| Features | Battery backup support is thereBackground initializatione-mail notificationOnline capacity expansion (expected fall 2004)Multiple card support (max. 4)Multiple array & Volume supportTime-delay spin-up for drives |
Behind the term "battery backup" is an extra module that helps to save all the cached information following a power-cut. Any information retrieved from storage or not yet written would otherwise be lost. Whereas this feature has long since been normal in the SCSI sector, 3Ware is now following LSI Logic in introducing it too - but the battery module has to be bought separately.
The possibility of expanding capacity while in operation, known as Online Capacity Expansion, is becoming more and more important. An extra drive can only be added to an array by means of this feature.
In addition to which, 3Ware Disk Manager 2 software now also supports up to four controllers and numerous arrays of different types, with up to 3 TG per controller - there is, however, no escaping a single, gigantic array covering all the available controllers, the StorSwitch architecture being an obstacle in this respect.
Details such as a command-line interface and delayed spin-up of all the drives (a SATA-II feature) round off the range of functions.
All that is hiding behind StorSwitch is the technical structure of the controller, based on point-to-point connections.
3Ware offers a total of five versions in the 9000 Series, including eight and 12 channel devices with individual ports, a multi-lane version and a low-profile version with four ports.
The disadvantage of Ultra320 SCSI: All the connected devices share the same total bandwidth.
