IBM Rolls Out Compact, Two-Core p5 Unix/Linux Server

by Timothy Prickett Morgan

With the Power5-based "Squadron" servers that IBM began rolling out last year, the company has taken a three-pronged attack on the server market. One type of Squadron box is designed to support its OS/400 operating system with auxiliary AIX and Linux partitions (the eServer i5), another is designed to only run Linux (the OpenPower), and the last supports AIX and Linux and sometimes OS/400 (the eServer p5). This week, the p5 line is getting a denser two-way machine, the p5 510.

The p5 510 is a rack-mounted machine that fits in a 2U form factor and comes with either a dual-core Power5 chip (making it the equivalent of a two-way symmetric multiprocessing server) or a Power5 chip with only one of its cores activated (the other is a dud and cannot be dynamically turned on). The p5 510 is nearly the same box as the OpenPower 710 server that was announced a few weeks ago (see IBM Launches Skinnier, 2-Way OpenPower Linux Server from The Linux Beacon, our Linux newsletter.) The p5 510 is different from the OpenPower 510 (as all p5s are distinct from all OpenPowers) in that it is a little more expensive when it comes to hardware pricing and it can support Linux as an auxiliary platform inside the p5's Virtualization Engine micropartitioning. This Virtualization Engine partitioning (which was created for the iSeries servers years ago) allows up to ten logical partitions, each with its own instance of an AIX or Linux operating system, to run on each processor core. There are some other differences between the two machines. The OpenPower 710 only comes with either one or two 1.65 GHz Power5 cores activated, while the p510 comes in four configurations--single- or dual-core Power5s running at either 1.5 GHz or 1.65 GHz. Neither the p5 510 nor the OpenPower 710 can support OS/400. You have to buy a high-end p5 570 (up to 16-way) or p5 590 (up to 32-way) to run OS/400 partitions.

According to Jeff Howard, program director for the pSeries Unix server line at IBM, the advent of the p5 510 marks the first time in about two years that Big Blue has had an aggressive offering in the 2U, two-way server space with its Unix platform. He says the 2U form factor--which allows more expansion room than the 1U pizza-box form factor--makes up about 40 percent of the Unix server market, and IBM has needed a more aggressive offering to go after Sun Microsystems and Hewlett-Packard in this area. While IBM could create a 1U form factor Power5 box with one or two cores, he said this seemed unlikely given that IBM wanted to focus its Unix efforts on more expandable boxes than it can offer with 1U frames. While he didn't say this, it could be that the thermal and form factor characteristics of the Power5 chips simply do not allow IBM to cram it into a 1.75-inch high space.

IBM has already said it will not offer anything below the 4U form factor in the OS/400-based i5 line because of the expandability those customers require, so the i5 520 is the smallest and cheapest machine they can buy. And, incidentally, the i5 520 costs a lot more than an i5 510 would, if IBM had the decency to offer a low-cost box to its loyal OS/400 customer base.

The p5 510 can support from 512 MB to 32 GB of main memory and has four drive bays that can support up to 587 GB of disk capacity. The base single-core 1.5 GHz variant of the p5 510 does not have any L3 cache, but the other three configurations do have 36 MB of L3 cache to boost performance. The p5 510 has a dual-channel Ultra320 SCSI controller, two Gigabit Ethernet ports, two USB ports, two Hardware Management Console ports (Yes, you have to buy an outboard box to use this server, and it costs a couple grand, by the way.), and three PCI-X slots. The p5 510 supports both the current AIX 5L 5.3, which supports micropartitioning on each Power5 core, and the prior AIX 5L 5.2, which can only support one partition per core. The servers can support the newer Cluster Systems Management (CSM) clustering software that IBM created a few years ago for AIX and Linux clusters; in the second quarter of 2005, the older High Availability Cluster MultiProcessor (HACMP) clustering software, which is prevalent in the IBM AIX installed base, will be supported on the machines.

Howard says IBM is aiming the p5 510 not just at high-performance computing customers who want to put them into clusters for running simulations, but also at retail and financial services companies that want to deploy AIX servers in stores or branch offices as well as among service providers and telecommunications companies that want to have the smallest possible Unix server and the smallest possible price tag for it.

The p5 510 will be available starting February 18, except for the two-core 1.5 GHz model, which will not ship until April 22. A base p5 510 with a single 1.5 GHz core, 512 MB of main memory, and a 73 GB disk drive costs $3,967. The server falls in the new D5 software group that IBM created a few weeks ago for AIX licenses; AIX costs $170 per core in this group, much lower than the $385 per core that IBM is charging on p5/i5 520 two-way and 550 four-way servers. A top-end, two-way p5 510 using 1.65 GHz cores with base memory and a single disk will sell for under $6,600, not including AIX. Just to show you how much more IBM loves to promote Linux than AIX, this same two-core machine with the OpenPower 710 label on it costs $3,999, not including Linux. The Virtualization Engine hypervisor layer that enables micropartitions costs extra on both the p5 and OpenPower flavors of this machine, by the way. IBM is offering so-called ValuePak configurations of the p5 that give customers beefed up machines, a free processor core activation, and discounts on other system components.