We are continuing our series of reviews of RAID controllers with SAS support. Today, we will talk about a product from HighPoint. Like other first-tier manufacturers, this company has been keeping up with the transition of hard disk drives with SAS interface from the category of special and fast products into the inventory of widespread server solutions and has released appropriate controllers in not one but two series: RocketRAID 43xx and 26xx. The former series includes controllers with onboard cache memory and a full-featured processor that computes checksums for RAID5 and RAID6. The RocketRAID 26xx series offers simpler products that process checksums by the driver, i.e. using the computing capabilities of the server. Roughly, they are the same as the well-known controllers of the RocketRAID 20xx series that support not only SATA but also SAS drives. Interestingly, all of them communicate across four PCI Express lanes whereas the 43xx series uses PCI Express x8.
Of course, we are more interested in RocketRAID 43xx which is a logical continuation of the RocketRAID 35xx SATA controller series. It is equipped with a PCI Express interface (PCI-X has been quickly abandoned by all manufacturers) and has a similar design. The processor frequency has increased from 800MHz to 1.2GHz, and the processor now has two cores. The heat dissipation has grown up, too. The previous series used to be cooled passively whereas every model of the SAS-compatible series comes with a cooling fan. Some features have been lost in the process of evolution, though. For example, the RocketRAID 43xx series currently offers models with no more than 8 ports whereas the RocketRAID 35xx series included a 24-port model. You will have to use expanders in order to connect a large number of hard disks.
Closer Look at HighPoint RocketRAID 4320
The HighPoint RocketRAID 4320 controller has eight internal ports. In other words, it is equipped with two SFF-8087 connectors. The series also includes two 8-port models (with two external connectors and with one external and one internal connector) and two 4-port ones (with an internal or external connector).
Besides the controller proper, the box contains a user manual, a disc with drivers, two cables (each for up to four devices), and a low-profile bracket. Yes, this is a low-profile card like every other in its series, excepting the model with two external connectors.
Take note of the network connector. It is meant for remote administration, making a nice addition to standard management tools (BIOS during startup, special software, or remote access via the OS running on the server).
All controllers of this series share the same processor, but have different amounts of onboard memory. The RocketRAID 4320 is not lucky in this respect. It only has 256MB like the 4-port models whereas the 8-port controllers with external connectors are equipped with 512 megabytes. HighPoint does not declare the memory speed, describing it only as “DDR-II ECC” but we can be more specific: the controller carries Qimonda HYB18TS12160B2F-3S chips with a frequency of 667MHz. RocketRAID 43xx series controllers support the same array types as the predecessor series, namely:
- Single HDD
RAID60, a stripe of RAID6 arrays, is missing in the list, but such a peculiar combination is not demanded much. Instead, there is RAID3 available – quite a rare type of RAID these days. It is close to RAID5, being its ancestor in fact, but differs from the latter in storing checksums on one specific disk (with RAID5, checksums are distributed uniformly among all the disks of the array) and all data are split into 1-byte blocks. You can easily guess why this array type is unpopular. The data segmentation method provokes problems with performance while the dedication of one disk for checksums guarantees that disk a much higher load than to any other disk in the array.
The controller came to us without a battery backup unit but was kind not to disable its caching algorithms for that reason. On our part, we want to remind you once again that information (and recovery thereof) is costly, so you should not use your RAID controller without a BBU. In case of a power failure, a lot of data can be lost in the cache, including housekeeping data. We can run controllers without BBUs for test purposes, but would never do so in real-life applications.