We continue our tests of RAID controllers on our new testbed that features high-performance hard disk drives with SAS interface. In this review we will discuss the best controller from the highly popular 3ware product line manufactured under the guidance of AMCC (as a matter of fact, Applied Micro Circuits Corporation consumed 3ware back in 2004). Now, however, there is a new owner of the 3ware product line: LSI Corporation recently (April 6th) acquired the 3ware RAID adapter business of AMCC.
We will check out if the architecture of the LSI 3ware 9690SA controller can cope with eight modern 15,000rpm hard disks.
Closer Look at LSI 3ware 9690SA
The 3ware 9690SA is the only series of RAID controllers from LSI 3ware family that supports hard disk drives with SAS interface. Other 3ware controllers support SATA and the 7506 series even supports PATA. The 9690SA series offers four models differing in what connectors they have. The 8I model we have got features two internal SFF-8087 connectors each of which provides up to four SAS ports. The -8E model has two external SFF-8088 connectors, and the -4I4E has one internal and one external connector. And finally, the -4I model is equipped with only one internal port.
Otherwise, the controllers in the series are all identical. They are all based on the same processor, equipped with 512 megabytes of DDR2 SDRAM clocked at 533MHz (desktop PCs used to have that much system memory just a few years ago!), and have PCI-Express x8 interface.
Interestingly, the controller’s main processor is the same as in the 3ware 9650SE we discussed in an earlier review. The marking differs in the serial number: AMCC Power PC405CR. 3ware still does not specify the processor clock rate but, judging by the marking, it must be 266MHz. This is not a high frequency if you compare it with competitor products. For example, the Promise SuperTrak EX8650 controller we tested earlier (by the way, you may want to read that review in order to understand this one better – we will be referring to it often) has a processor frequency of 800MHz, and the senior model from the same SuperTrak series has a processor frequency of 1200MHz. On the other hand, the 3ware controller’s processor is architecturally different from the popular Intel XScale, making direct comparisons incorrect.
Besides the controller, the box contains a brief user manual, a disc with drivers and software, a back-panel bracket to install the controller into low-profile system cases, and two cables.
The cables are CBL-SFF8087-05M for connecting racks with SFF-8087 connectors. If you want to connect HDDs directly to the controller, you must use CBL-SAS8087OCF-06M cables that end in four disk connectors.
The controller supports nearly every popular type of a RAID array you can build with four HDD ports, namely:
- Single disk
RAID60 is missing here (it is a stripe of two RAID6 arrays), but that’s not a big loss. Most users will prefer to complement fault tolerance with either higher capacity (RAID6) or higher speed (RAID10).
In our previous test session the Promise EX8650 refused to enable deferred writing without a backup battery unit, which affected its writing performance greatly. Therefore we tried to find a BBU for the 3ware controller’s cache even though the controller allowed to force deferred writing on even without one. We just did not want to take any risk that time around.
As opposed to 3ware’s previous controller series, the 9690SA supports a new type of BBUs called BBU-Module-04. Such batteries can be used together with 9650SE and 9550SXU controllers, too. The difference is obvious: the BBU is now installed not on the controller but on a separate card that occupies another slot in your system case. It is not actually plugged into a mainboard’s expansion slot, but takes the place above an expansion slot that has an appropriate bracket in the back panel. The BBU is connected to the controller with a cord and a special tiny daughter card that is fastened with two plastic poles to the controller and communicates with the latter via a special connector.
The controller is still managed in two ways: via BIOS or through the exclusive OS-based 3DM application. There are versions of 3DM available for Windows, Linux and FreeBSD in both 32-bit and 64-bit variants.