Highpoint Takes On Adaptec's SAS Controller

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1 SAS/SATA RAID Solutions Highly available storage offering flexible configurations up to 80TB. Serial Attached SCSI Read about SAS SCSI and about advantages over parallel Highpoint Takes On Adaptec's SAS Controller 7:00 AM - December 19, 2008 by Patrick Schmid and Achim Roos Source: Tom's Hardware US Table of content 1 - David Versus Goliath, Highpoint Versus Adaptec 2 - Serial Attached SCSI And SATA 3 - Highpoint Rocket RAID 2540X4 4 - Highpoint s Web GUI And Array Creation 5 - Adaptec RAID Adaptec Array Creation and Power Settings 7 - Comparison Table & Test Setup 8 - I/O Performance 9 - RAID 0, 10, 5 Throughput 10 - Conclusion David Versus Goliath, Highpoint Versus Adaptec Highpoint was one of the first companies to offer capable and flexible storage controllers for mainstream markets. These components found their way onto enthusiast class motherboards, which had lacked storage features until a few years ago. Or, they were sold on controller cards to enable professional RAID capabilities at an affordable cost. However, the consolidation of the storage market resulted in ample availability of storage connectivity, from Serial ATA (SATA) for the mainstream to Serial Attached SCSI (SAS) for servers and workstations. Storage vendors such as Highpoint now focus on offering a better value for business customers than the more entrenched companies like Adaptec. We analyze two entry-level SAS RAID controllers to see how they compared.

2 RAID Controller Options It has become tough for storage vendors to come up with controller or host bus adapters that can offer significantly better features than those of existing products. Host-based RAID controllers such as the RAIDCore controllers offer maximum flexibility, but they depend on the performance of their host systems. The software layer called VST Pro has been available for use with 3 rd party storage controller such as Intel on-board controllers for a while. Most mainstream on-board RAID solutions are considered host-based RAID as well, by the way. Software RAID, which is entirely executed on a host operating system, is not always the best choice, as the storage array s performance depends on its host. Hardware RAID Many people consider hardware-assisted RAID controllers the only real option if you take your storage seriously. So-called hardware RAID utilizes a dedicated controller card, which often comes with its own firmware and management tools, an accelerator chip for parity operation (XOR engine) and a dedicated cache memory. These controllers work on most operating systems (with drivers required), but they don t require a lot of resources, unlike the solutions mentioned above. Is Budget RAID Good Enough? Highpoint has been coming up with all sorts of unusual solutions, from small form factor host adapters (the Rocket RAID 2680 is only 3. 3 inches long) or SAS RAID controllers at SATA pricing. We decided to have a look at the Rocket RAID 2640X4, which is a sub-$150 4-port SAS controller with standard RAID capabilities for the PCI Express bus. Can it beat Adaptec s entry-level 4-port SAS model RAID 5405, which costs roughly $350? Serial Attached SCSI And SATA There are many reasons to go straight for a SAS-based RAID controller card. The first and most important is the compatibility of these host adapter cards, as the SAS interface supports the necessary protocols to also handle SATA hard drives, and both use the same

3 basic connectors. SAS stands for Serial Attached SCSI, and represents a serial implementation of the traditional parallel SCSI bus protocol (which is known as the SAS SCSI Protocol, or SSP). However, SAS controllers also implement STP, the SATA Tunneling Protocol, allowing controllers to operate either SAS or SATA drives. In contrast, no SATA controller supports SAS drives. Why Choice Is So Important If you are familiar with the storage market, then you already know that there are mainstream drives available in capacities of up to 1. 5 TB, while professional drive models go up to 300 GB (with 600 GB coming soon). The professional drives are always based on 10,000 RPM or 15,000 RPM spindle speeds (or flash memory), use the 2.5 or 3.5 form factor, and the SAS interface, which allows two distinct links to the controller for performance or redundancy reasons. Drives and controllers are many times more expensive than those used for mainstream desktop machines, making them only attractive for business and enterprise applications where high performance may be important enough to justify the cost. However, large storage capacities for near-line and offline storage can only be realized through high-capacity drives. Examples of near-line storage use are daily backups, while offline storage refers to archiving and similar storage applications where the data doesn t require fast or direct access. Large capacities require mainstream drives with SATA interfaces, which most of the drive manufacturers modify to fit the durability and reliability requirements of enterprise applications. Hence, Hitachi has its Ultrastar 7K1000, Seagate offers the Barracuda ES, etc. If you want to combine high performance and high capacity in a single architecture, you have to purchase high capacity storage based on Serial ATA and high performance drives based on SAS. The controllers we reviewed do exactly this. Where SAS Is Really Impressive SAS has multiple advantages over SATA. Both serial standards are based on point-to-point interconnects, but SAS supports expanders to allow more drives to be attached. Think of these as switches for SAS. Up to two edge expanders for up to 128 drives each can be connected to a SAS controller, and fan-out expanders are used to connect up to 128 edge expanders. SAS cables are available for individual connects (SFF-8482 cables), but most controllers come with SFF-8470 ports, which route four SAS connectors to backplanes and similar devices. These are also used by InfiniBand. While SATA is based on half-duplex communications, SAS is a full-duplex link, also supporting port aggregation and dual-link mode to increase performance or to create redundant connectivity. Now let s look at Highpoint s sub-$150 SAS offering. Highpoint Rocket RAID 2540X4

4 The Rocket RAID 2640 X4 is Highpoint s PCI Express SAS RAID controller card with four internal ports. Model number 2642 offers two internal and two external ports, while model 2644 was designed with four external ports; there is also a Rocket RAID 2680 card with eight internal ports. All of these products are based on four-lane PCI Express interfaces, but they may also be operated on x1 PCI Express connections at reduced performance. The Rocket RAID 2640X4, which we received for review, is a low profile card that is based on a Marvell controller and four individual SFF-8482ports. The most interesting detail about this storage controller is its price tag of less than $150. It even comes with a threeyear warranty. Highpoint supports the common RAID levels 0, 1, 10 and 5, native command queuing, multiple arrays per controller, array roaming for easy transfer to other Highpoint RAID controllers, online capacity expansion, RAID-level migration on the fly, notification, and I2C-based enclosure management. The feature list is as long as the lineup of supported operating systems, including Windows 2000 and up, the major Linux distributions such as Fedora, RedHat and Suse, Free BSD and Mac OS However, you have to pick a Rocket RAID 4000 series card to get RAID 6 support with double parity. The Green Feature Although Highpoint doesn t make a big fuss about it, the company now offers a green feature as well, which is meant to stop all the drives spindle motors to save power when they are idle. While such a feature doesn t make sense for performance systems to ensure storage availability, home servers or small business storage systems may very well work in green mode outside office hours. We knew about the feature, but we couldn t find it on the management console. As Highpoint told us, it has only been implemented on the Web GUI, where we were able to turn it on. However, our Fujitsu MBA-3174RC drives would not spin down at all, so we contacted Highpoint again. We were told to use Seagate drives, as these were validated for the feature; we grabbed two Seagate Cheetah 15K. 6 drives and quickly created a RAID 0 array, but the drives again would not spin down. Unfortunately, the feature doesn t seem to be working at all and we cannot vouch for its functionality at this time.

5 Performance We ran our standard benchmark suite, which we use to test all sorts of storage controllers. In the streaming read/write tests, the Rocket RAID 2640X4 does very well in RAID 0, where it delivered the same ~470 MB/s sequential read throughput as the Adaptec 5405 card. Writes were only marginally slower, and RAID 5 performance was even superior to the numbers we received from the Adaptec controller. In RAID 10 mode, however, Adaptec implemented a more efficient read algorithm that delivers almost 450 MB/s, while Highpoint starts at 230 MB/s throughput and speeds up to 420 MB /s as queue depths increase. RAID 10 write performance is similar again. Clearly, Highpoint can match Adaptec s performance using four 15,000 RPM Fujitsu MBA3174RC drives. However, sequential throughput is only one half of the performance evaluation we also have to analyze I/O performance. Whether we look at the database, file server, Web server or workstation benchmarks, Adaptec s 5404 always provides 5% to 15% more I/O operations per second than the Highpoint Rocket RAID 2640X4. Clearly, the missing cache memory has an impact. Highpoint s Web GUI And Array Creation We browsed Highpoint s website looking for the latest drivers for the Rocket RAID 2604X4 card, but could not locate them. In fact, we had to manually search the drivers directory to find the 32-bit drivers for Windows Server The bug was resolved once we told Highpoint about it. The spin-down issue, however, is still there, and the feature still can only be accessed in the Web GUI. Web GUI

6 RAID Array Creation

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8 Adaptec RAID 5405 Six months ago, we looked at Adaptec s 5-series SAS controller family, which provides excellent performance at reasonable cost. At that time, we examined the model 5805, which provides eight internal ports (two InfiniBand-type connectors) as well as Adaptec s 1.2 GHz dual-core storage processor with lots of memory (512 MB DDR2). This time we received the entry-level model 5405, which is the cheapest way of getting an Adaptec storage adapter. It comes with a three-year warranty and we found it at prices of $350 and up. Comprehensive Feature Set The technical details here read similarly to those of Highpoint s Rocket RAID 2640X4 card, but Adaptec offers more advanced features. There is a PCI Express interface as well, but Adaptec utilizes 8 lanes instead of 4, which can provide more bandwidth for high-end applications (though in everyday life, the difference should be rather small in the entrylevel category). The RAID 5405 card comes with 256 MB DDR2 cache memory, which isn t available on the Highpoint card at all. The same applies to the battery backup unit (BBU). There is one SFF-8487 internal connector that holds all four ports, but Adaptec includes a fan-out cable to let you attach four drives directly. Finally, Adaptec has the more comprehensive RAID support, offering RAID levels 0, 1, 1E, 5, 5EE, 10, 50 and 60 (E stands for spares). Both cards, of course, support JBOD. Slightly Better Performance

9 As mentioned in the evaluation of the Highpoint card, Adaptec offers slightly higher throughput and clearly better I/O performance. If you want your SAS controller to deliver maximum performance, there is no way around the Adaptec 5-series card. Power Management Works We used the same Fujitsu drives to try the Intelligent Power Management feature, which according to Adaptec, can save up to 70% of power clearly a bold statement. The powerdown mode worked fine, switching off the drive s spindle motor after a pre-set idle period, but the slow down mode didn t work. According to Adaptec, the Fujitsu drives currently don t support this mode. With that said, each drive went from 7.5 W to 4.8 W idle power in power-saving mode, which added to total system savings of 18 W when all four drives were spun down. This is nowhere near the 70% power savings claimed maybe when looking at using peak power as the base but if you add up the savings for hundreds or thousands of hard drives, the difference becomes significant. We d definitely turn on such power saving mode for storage and backup servers that don t have to be instantly available. Total Idle Power Drive Power 5V 12V 5V 12V System Power (W) Reduction Per Measurements Power Drive (W) Standard W Power Down W Adaptec Array Creation and Power Settings Buyers of the Adaptec 5-series RAID card family will use the Adaptec Storage Manager, which offers helpful wizards and easy management of your hardware. RAID Array Creation

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11 Adaptec Power Settings

12 Comparison Table & Test Setup Manufacturer Adaptec Highpoint Model RAID 5405 Rocket RAID 2640X4 Internal connectors 1x SFF x SAS / SATA External Connectors N/A N/A Cache 256 MBDDR2-400 ECC N/A Profile Low Profile Low Profile Interface PCI Express x8 PCI Express x4 XOR Engine 1.2GHz Dual Core RAID on Chip Marvell88SE6445 RAID Level Migration Yes Yes Online Capacity Yes Expansion Yes Multiple RAID Arrays Yes Yes Hot Spare Support Yes Yes Battery Backup Optional Unit N/A RAID 5 Init 35 Min 26 Min Supported RAID Modes 0, 1,1E, 5, 5EE, 6, 10, 50, 60, JBOD 0, 1,5, 10, JBOD Fan No No Windows(2000, XP, x64, 2003, 2008, Vista (32-Bit and 64-Bit) WindowsXP, Server 2003/2008, Vista, Red Hat Linux (Fedora Core, Red Enterprise Linux (RHEL), SUSE LinuxEnterprise Supported OS Hat Enterprise / CentOS, Server (SLES), SCOOpenServer, UnixWare, Sun Solaris 10 x86, FreeBSD SuSE) Mac OS X 10.4.x and above FreeBSD

13 Linux Open Source Other Features Copyback Hot Spare Warranty 3 Years 3 Years Price $340 $140 Test Set Up System Hardware Processor (s) Platform RAM System Hard Drive Test Hard Drives (8x) Mass Storage Controller (s) Networking Graphics Card System Hardware Performance Measurements 2x Intel Xeon Processor (Nocona core) 3. 6 GHz, FSB800, 1 MB L2 Cache Asus NCL-DS (Socket 604) Intel E7520 Chipset, BIOS 1005 Corsair CM72DD512AR-400 (DDR2-400 ECC, reg. ) 2x 512 MB, CL Timings Western Digital Caviar WD1200JB 120 GB, 7, 200 RPM, 8 MB Cache, UltraATA/100 Seagate Savvio 10K. 2 ST973402SS 73 GB, 10, 000 RPM 16 MB Cache, SAS Intel 82801EB UltraATA/100 Controller (ICH5) Adaptec RAID 5805 Broadcom BCM5721 On-Board Gigabit Ethernet NIC On-Board Graphics ATI RageXL, 8 MB c't h2benchw 3. 6 PCMark05 V1. 01 IOMeter Fileserver-Benchmark Webserver-Benchmark I/O Performance Database-Benchmark Workstation-Benchmark Streaming Read and Write Benchmarks System Software& Drivers OS Microsoft Windows Server 2003 Enterprise Edition, Service Pack 1 Platform Driver Intel Chipset Installation Utility Graphics Driver Default Windows Graphics Driver I/O Performance Depending on the I/O benchmark, the Adaptec RAID 5405 provides marginally or up to 15% better I/O performance than Highpoint s low-budget offering. Increasing command queue depths works in favor of Adaptec, likely because of its 256 MB DDR2 cache memory.

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15 RAID 0, 10, 5 Throughput RAID 0 Throughput

16 RAID 0 performance is almost equal. Adaptec achieves slightly higher performance, but the difference really is too small to make a big deal over. RAID 10 Throughput

17 RAID 10 read performance is much higher on Adaptec s RAID 5405 card, as it seems to be using all four hard drives for read operations and reaches almost 450 MB/s, while the Highpoint drive is limited to 240 MB/s at low command queue depths. Write performance, however, is similar with both cards. RAID 5 Throughput

18 Adaptec and Highpoint reach the same 350 MB/s read throughput for sequential operation in RAID 5, but Highpoint provides better performance on degraded RAID 5 arrays (where one drive is disabled or being rebuilt). Conclusion Highpoint did a great job on its hardware. The RocketRAID 2640X4 provides almost the same throughput as Adaptec s RAID 5405 entry level controller when running RAID 0 or RAID 5. Still, it cannot match Adaptec s RAID 10 read throughput, nor its I/O performance, which is 5% to 15% better. Considering that the Highpoint card is a rather simple product that is based on an all-in-one SAS controller solution by Marvell (no cache memory, x4 PCIe), the result is certainly impressive. Highpoint s main point, the price tag of under $150, makes the card appear even more appealing. Lost On the Finishing Line Unfortunately, there were some issues. Taken individually, each wouldn t be a big deal, but added up, they demonstrate that Highpoint still has some homework to do. Initially, not all drivers were available on the support Web site, which could cause serious problems for administrators who are in a hurry and need the latest software to continue. The idle

19 disk spin-down feature, which can be configured to shut down the drives spindle motors after a certain number of minutes, did not work with any of the test hard drives, and it can only be configured on the Web interface, not on the installable management software. In addition, the feature set isn t as comprehensive as the impressive lineup we found on the Adaptec controller which, by the way, matches the functions of Adaptec s more advanced multi-port SAS RAID controller cards. Should Cost Decide? The Highpoint RocketRAID 2640X does a great job as a basic RAID controller device. It matches Adaptec in most disciplines, but it doesn t beat it. If you can live with the fact that the Highpoint offering may not be as thorough, mature, or elaborate as Adaptec s product, you ll get a powerful device at a very affordable price. However, you really should ask yourself one question: does it make sense to spend hundreds of dollars on SAS hard drives just to save $200 on the controller card? That's a question for you to answer. Tom's Hardware -