AMCC 3Ware 9550SX-8LP review

As with Adaptec, AMCC has lagged substantially behind LSI Logic in getting SATA II RAID controllers to market, but it’s arrived with a bang. It’s introduced a family of five new controllers and, in this exclusive review, we take a look at the 9550SX-8LP, which delivers eight SATA ports.

The 9550SX-8LP supports both 3Gb/sec speeds and NCQ. The latter aims to improve performance for random I/O operations by taking multiple requests for disk operations and reordering them so they’re executed more effectively. For normal operations, the drive heads have to deal with requests in the order they’re received, which results in inefficient operations. Unlike Adaptec’s 2820SA, the 9550SX-8LP also supports port-multiplier technology, which allows multiple drives to be attached to a single port. This could prove useful in servers equipped with suitable multipliers on their backplanes, as more drives can be connected to the controller and cable-related clutter reduced as well.

The 9550SX-8LP is a half-height PCI-X card and is narrower than the 2820SA, making it a better bet for rack-server apps. The SATA ports are located on the top surface of the card and presented as five connector blocks, each with an upper and lower port. Don’t be fooled by the two blocks set further back: although they also have two ports each, only the upper ones are active. The card comes with 128MB of PC2-3200 embedded cache memory, which can’t be upgraded, but AMCC does offer an optional battery backup unit.

Configuration starts during system boot-up, where a simple BIOS screen allows you to create, delete, modify or rebuild arrays and add a hot-standby drive to an existing array. The card can manage the usual RAID suspects, but JBOD configurations are no longer supported and won’t appear as available units to the OS. For the latter, AMCC now uses the concept of single-disk units, which can take advantage of features such as caching.

Management options are reasonable, as AMCC’s 3DM 2 software allows the controller to be managed locally and remotely using a browser over secure HTTPS sessions. The interface provides good levels of access to the drives and you can monitor errors, schedule regular array rebuilds and ask for alerts to be sent to an email address. Overall, 3DM 2 offers a decent range of features, but we found that although Adaptec’s Storage Manager didn’t support HTTPS, it was better designed. For instance, Adaptec’s software provided a lot more detail about the controller and arrays, along with superior alerting facilities.

For performance testing, we employed the same Supermicro dual 2.4GHz Xeon system as used to test the Adaptec 2820SA. With a single Western Digital 3Gb/sec SATA hard disk attached to the controller, Iometer reported a raw throughout of only 75MB/sec when configured with two workers and 64KB sequential read requests. With two drives configured in a RAID0 stripe, the card still lagged behind Adaptec at 155MB/sec. However, with a three-drive stripe, the 9550SX returned 206MB/sec for read operations – around 18MB/sec faster than the 2820SA.

There’s little to separate the 9550SX-8LP and 2820SA overall, but Adaptec’s planned release of its Advanced Data Protection Suite makes it a better long-term investment.