ProLiant 6000 with the Pentium II Xeon Processor

Serious scalability in a quad-Xeon server

I recently tested Compaq's ProLiant 6000 with the Pentium II Xeon Processor,the server that marks Compaq's entry into the quad-Xeon market. The system Ireviewed includes four 400MHz Pentium II Xeon (Deschutes Slot 2 architecture)processors.

When I received the ProLiant 6000, the first thing I wanted to do was seethe Xeon processor. To satisfy my curiosity, I removed one of the system'schips. It slid out easily and was soon in my hands.

The first time I saw a Pentium II, processors stopped looking like chips tome and started looking like field replaceable units (FRUs in IBM terminology)from mainframe-class systems. I've spent my share of time in shops withliquid-cooled mainframes, but I never thought I'd see a liquid-cooled PCprocessor. Compaq ships each Pentium II Xeon processor with what looks like a small radiator, a mechanism that transfers heat away from the chip's primaryheat sink. Compaq calls this device the evaporator plate and water-cooledheat pipe. The mechanism lends a lower profile to the system board than thestandard heat sink.

Replacing the ProLiant 6000's processor was easy. Compaq'sprocessor-insertion guides make the process almost foolproof.

System Hardware
A ProLiant 6000 with four Pentium II Xeon processors supplies a fair amountof processing power, and the system has the I/O capacity and expansioncapabilities to help you harness the processors' power. The ProLiant 6000'sstandard configuration includes one hot-swappable hard disk cage, but you canadd two more cages. Each of the machine's cages can hold up to six 1" harddisks or up to four 1.6" hard disks. These numbers mean that if youconfigure the system with three cages and fill each cage with 9GB hard disks,you can store 162GB of data in a unit the size of a two-drawer filing cabinet. Acouple years ago, I would have wondered what kind of network would ever needthat much storage, but if you use online analytical processing (OLAP)databases and support users who rarely delete files, you'll appreciate theoption to expand to 162GB. In addition to the hot-swappable hard disk cages, thesystem has six half-height 5.25" drive bays. One bay holds a 5.25"disk drive, one holds the system's CD-ROM drive, and four are empty.

The ProLiant 6000 has three Ultra Wide SCSI-3 buses that support data ratesup to 40MBps. The system I tested includes Compaq's Smart Array 3100ESController, a 64-bit PCI card that has extended SCSI connectors that connect toeach of the hot-swappable hard disk cages. With these connectors, the systemdoesn't require SCSI cables to the array controller. This feature makes for aclean installation and eliminates the need to remove cables when you remove thearray controller. The ProLiant 6000 has 56MB of onboard, battery-backed,read-write cache that enhances the disk array's performance. The array supportsRAID 0 (data striping with no fault tolerance), RAID 1 (mirroring), RAID 0+1 (amirrored RAID 0 stripe set), RAID 4 (fault tolerance with a dedicated paritydrive), and RAID 5 (fault tolerance with parity information spread across alldrives). (For more information about RAID, see Joel Sloss, "RAID: EnhancedDisk Storage for Windows NT," August 1997.)

Three PCI buses with a total of ten I/O expansion slots give the ProLiant6000 plenty of expansion capacity. Bus 1 and bus 2 each hold two 32-bit slots.Bus 3 holds five 64-bit slots, two of which include the extended SCSIconnectors. Compaq designed the system's one ISA slot to hold a modem board. Thesystem has a standard set of I/O interfaces. The integrated PCI video controllercomes standard with 2MB of memory and supports resolutions up to 1024 * 768pixels. The standard configuration also includes two serial ports and a parallelport. The keyboard and mouse ports use small PS/2 connectors.

The system supports Error-Correcting Code (ECC) RAM. It uses 60 nanosecond(ns) Enhanced Data Output (EDO) DIMMs up to 256MB each. Eight banks of fourDIMMs in matched sets support a total of up to 8GB of memory.

Compaq supplies a Netelligent Dual 10/100 TX PCI UTP Ethernet controllerand Compaq Advanced Network Control Utility software. You use the software toconfigure the Netelligent Ethernet cards; when you use it with a pair ofdual-port or single-port Ethernet cards, the utility lets you set upfault-tolerant network connections. The ProLiant 6000 also comes withfault-tolerant power configurations. You can configure the server with as manyas three load-balancing, hot-pluggable, redundant power supplies. Depending onyour system configuration's power load, you might require two power supplies forsystem operation and a third power supply for fail-safe redundancy.

Management Software
Compaq ships the ProLiant 6000 with several systems management supportutilities, including Compaq Insight Manager, Compaq Integrated Management LogViewer, Compaq Array Configuration Utility, Compaq Power Down Manager, andCompaq Power Supply Viewer. These systems management features let the ProLiant6000 work with any enterprise systems management product.

Companies that make the effort to engineer their products for reliabilityand easy detection of problems always impress me. For years, Compaq has beengoing a step further, providing features that predict potential componentfailures before problems occur. Compaq Insight Manager provides thisfunctionality by monitoring key aspects of component performance. For example,the software monitors the length of time hard disks take to spin up. Whenspin-up time starts to take longer than usual, Compaq Insight Manager alertsusers that the drive might be failing. Compaq supports the ProLiant 6000 with a3-year onsite warranty, which includes prefailure replacement of processors,memory, and hard disks when Insight Manager reports a degraded component.

Compaq Integrated Management Log Viewer displays the system-level hardwareevent log that the ProLiant 6000 maintains. Compaq Array Configuration Utilitydisplays configuration information about the Smart Array 3100ES Controller andlets you configure the controller. The utility is also a convenient tool fordisplaying information about your SCSI devices and device IDs.

Compaq Power Down Manager lets you disable the ProLiant 6000's externalpower switch or set the external power switch to shut down NT before poweringdown the system. Compaq Power Supply Viewer saves you from wondering whetheryour redundant power supplies are truly redundant. The utility displays powerconsumption as a percentage of available power, and it lets you know whether theserver would survive a failure of one of your power supplies. Compaq PowerSupply Viewer also displays AC line and DC output voltage levels.

How Does It Perform?
Because server vendors are increasingly standardizing computers' components,you can often attribute performance differences between systems that contain thesame class of processor to I/O subsystem performance. When I ran the WindowsNT Magazine Lab's usual file-server benchmark tests on the ProLiant 6000, Ididn't expect results dramatically different from my recent benchmarks of HP'sNetServer LH 3, a dual-450MHz Pentium II (Deschutes Slot 1) system. (For moreinformation about the system, see "NetServer LH 3," December 1998.)The LH 3 has five disk spindles on a caching controller, and the ProLiant 6000has only three disk spindles in its RAID 0 data array. Nevertheless, theProLiant 6000 performed much better than the LH 3. I ran Bluecurve's DynameasureCopy All Bi-directional tests with a Special File workload and a 24MB test dataset to measure both systems' performance. The ProLiant 6000 peaked at17,097KBps, almost 50 percent more throughput than the dual-processor systemproduced.

During the peak period of the ProLiant 6000 benchmark test in which Irecorded 17,097KBps of throughput, the four processors' average CPU utilizationwas 58 percent, 53 percent, 47 percent, and 20 percent, for an averageutilization of 45 percent. Because of these processor loads, I figured thatremoving one or two processors from the ProLiant 6000 would affect performanceonly minimally. To test my theory, I rebooted the server in a two-processorconfiguration, then ran the Dynameasure benchmark again. The ProLiant 6000'speak throughput dropped by only 8.6 percent--­throughput reached15,629KBps, with an average CPU utilization of 66 percent. This test led me tothe conclusion that the file-server application that the Dynameasure testsimulates doesn't benefit much from a four-processor ProLiant 6000 unless youincrease the disk subsystem's throughput capacity.

You'd probably like a performance improvement of more than 10 percent foran investment in 100 percent more processors. However, if you invest in aquad-Xeon system to run only a file-server application, you'll probably alsoinvest in an I/O subsystem that better matches throughput capacity to thesystem's CPU capacity. Alternatively, you might invest in a quad-Xeon system torun back-office applications that are more CPU intensive than file-serverapplications and benefit more from the ProLiant 6000's four processors.

Is It for You?
The quad-Xeon ProLiant 6000 is a solid server with substantial expansioncapacity. The system might work very well for a small business. The businesscould start with Model 1-128, a single-processor unit with a modest 128MB of RAMand standard SCSI controllers. Then, if the company needed more power, theProLiant 6000 could grow to hold four Xeon processors, 8GB of RAM, and threeSCSI channels or a fibre channel to support its RAID arrays.