Apple Launches G5 Server, RAID Storage

by Timothy Prickett Morgan

If you are an Apple Computer enthusiast or you just want to get a piece of the PowerPC G5 Linux cluster running at Virginia Tech to do commercial work, Apple has finally launched the Xserve server running the G5 processor. The launch was made at the Macworld 2004 Expo in San Francisco. Apple has also launched a RAID storage array for the machines dubbed the Xserve RAID that works with MacOS X Server as well as Windows and Linux boxes.

The new Xserve server looks a lot like other rack-mounted X86 machines in terms of its core functionality. It fits in a 1U form factor (like prior G4 Xserves) and can support two-way symmetric multiprocessing using the G5, which is also known as the PowerPC 970. The G5 is a trimmed down implementation of the 64-bit Power4 processor from IBM that supports a frontside bus for each processor that runs at half the clock speed of the chip's core. (Just like the Power4 processors do inside IBM's own iSeries and pSeries machines.) That means a 2 GHz G5 processor has a frontside bus running at 1 GHz, delivering 16 GB/sec of bandwidth. This is a lot more than the 167 MHz frontside bus for the 1GHz PowerPC G4 could deliver. The G5 processors are available running at 1.6 GHz and 1.8 GHz, but when they will be available in the Xserve machines is unclear.

The Xserve G5 supports up to 8 GB of DDR SDRAM with ECC protection, up to 750 GB of internal disk storage (three 250 GB Serial ATA drives), has two Gigabit Ethernet ports on the motherboard, plus two FireWire 800 ports, one FireWire 400 port, two USB 2.0 ports, and a serial port. The G5 server can support one full length PCI-X cards running at 133 MHz or two short PCI-X cards running at 100 MHz. The Xserve G5 runs the "Panther" Mac OS X operating system, which is based on the open source BSD distribution of Unix and which is been refitted with a Mac emulation environment. This gives Mac customers a potentially huge base of applications, if Unix application developers decide to port their code to Mac OS X. In any event, a base machine with a single 2 GHz G5 with 512 KB of L2 cache, 512 MB of main memory, and 80 GB of disk costs $2,999. A two-way version of the machine with 1GB of main memory costs $3,999, and a two-way machine with 2 GB of main memory and three 250 GB disks costs $6,599. A single drive bay version of the Xserve G5 with more airflow for cooling sells for $2,999 with two 2GHz G5s and is known as the cluster node.

The Xserve RAID array is a 3U chassis that can support up to 14 hot swap, 7200 RPM Ultra ATA drives. While many storage array makers have focused on using the fastest SCSI disk drives running at 10K RPM or 15K RPM for their arrays, which are used primarily as direct-attached storage used to be in the old days, Apple has taken the path of using low-cost ATA drives for server storage (much as many NAS array makers have done). The Xserve RAID attaches to servers via a Fibre Channel link, just like other modern arrays do. Each ATA drive attaches to its own channel that in turn links to the Fibre Channel fabric, which Apple says means that capacity and I/O performance scale as drives are added to the Xserve RAID devices. The Xserve RAID supports RAID levels 0, 1, 3, 5, and 0+1 using its internal controllers, and can support RAID 10, 30, and 50 by mixing hardware RAID on the arrays with software RAID on the Xserve servers. The base machine has four 250 GB ATA drives, 256 MB of cache, dual RAID controllers, and dual Fibre Channel server links for $5,999.

Apple says that, based on suggested retail Web pricing as of December 30, it can deliver 3.5 TB of storage in the Xserve RAID for $10,999 or $3.14 per GB. This is one third the price of much higher performing SCSI arrays from Dell, and a lot less than what Apple reckons is the competition from IBM, HP, and Sun in the entry disk array market. A Dell/EMC CX200 array with 2.1 TB of storage costs $18,999 or $9.05 per GB, by Apple's math, and an HP StorageWorks 1000 array with the same capacity costs $23,925 or $11.39 per GB. IBM's FASt200 3542-1R array is a similar 3U RAID box and it costs a whopping $51,895 or $24.71 per GB in a 2.1 TB configuration. A Sun StorEdge 6120 array requires two 3U chasses to get to 2.04 TB and costs $74,600, or $36.57 per GB.

Apple is clearly less worried about the performance of its arrays than it is on price, and given that all of the fast I/O and disks of modern arrays only really come into play with big database-driven and transaction-driven applications, Apple may have a point to make and some money to make, too. The Xserve RAID array can pack 49 TB of disk capacity in a 42U rack for a cost of about $154,000. That's pretty impressive, and it will be important to Apple's customers in the digital media and emerging high performance computing markets.