IBM Proposes One Computer to Run Entire Internet

Dreaming big; IBM looks to host entire internet on a single modified Blue Gene supercomputer

Thomas Watson, founder of IBM, is oft misquoted as stating that the world really only would need five computers. Ironically the frequently used, erroneous quotation may come to true by the very hands of the business Watson created.

IBM launched an Epic project with an almost unfathomable goal -- to develop a single supercomputer capable of running the entire internet as a web application. The project, codenamed Kittyhawk (detailed in a white paper by IBM) created quite the stir in internet technology community.

While the software details descend quickly into the realm of the cerebral, one number that jumps off the page is the estimate for the number of cores and memory for the finished proposed system -- 67.1 million cores with 32PB of memory.

The system is based on IBM's Blue Gene/P architecture, which takes millions of cores and arranges them in a hierarchal architecture. At the lowest level four 850 MHz Power PC cores run on a single chip, with built in memory controllers and interconnects. The next level up is the card, which contains 32 of these quad core chips known as "nodes." Up a level, 16 cards compose a midplane. A server rack has two midplanes, yielding a total of 1024 nodes, or 4096 processors. Each server rack has 2TB of memory to play with. A maximum of 16,384 racks can be networked to yield the finally staggering metrics. As each rack has an I/O bandwidth of 640Gb/s, a "full" 67.1m core system would sport 10.4Pb/s of bandwidth.

The design is certainly not unproven technology -- IBM's Blue Gene architectures own 4 of the top 10 spots of the list of fastest supercomputers on the planet, including the top spot, which is occupied by IBM's Blue Gene/L. IBM's Blue Gene/L architecture is the successor to its P architecture. The Kittyhawk project, initially designed with the Blue Gene/P architecture, will likely make the eventual switch to the more powerful and efficient "L" architecture.

IBM argues that there are many advantages to using large SMP (symmetric multi-processing) systems for internet hosting. Such systems beat clusters in power efficiency and space requirements. However, clusters beat SMPs in terms of pricing and availability, due to the ability to utilize generic commercial hardware for much of the system. This had led companies such as Sun Microsystems, Amazon.com, Google and Microsoft to adopt cluster hosting centers, which provide the companies with the ability to flexibly increase their capacity as demand mandates.

While it acknowledges the benefits of clusters, IBM feels that by using its proven, scalable Blue Gene architecture it can provide box solutions for web software jobs which beat cluster solutions at their own game. IBM says that by choosing Blue Gene, web customers would be able to obtain large savings due to the more efficient infrastructure.

The company also points out that a fast-growing web company often has need for bandwidth outpaced by demand. Their web hosts can only add so much capacity at a time, due to the long validation and construction process needed to expand clusters. IBM says its Blue Gene system is validated per rack, so can be quickly deployed for increased capacity. Additionally, it points out that clusters have relatively high failure rates, leading to loss in service or need for backup systems, while its racks seldom fail.

IBM's current implementation is in a dead heat with current clusters, according to the company. It can currently run most standard web applications, including Linux, Apache, MySQL and Ruby on Rails. Its conclusions are based on the SPECjbb2005 Java performance benchmark, which yielded an impressive 9565 Business Operations per second (BOPS) for the current implementation, and LAMP (Linux Apache MySQL Perl/Python) software benchmarks, which yielded similar encouraging results. IBM's researchers feel that this is only the start and that an optimized version will blow away clusters. They stated in the paper, "We hypothesize that for a large class of web-scale workloads the Blue Gene/P platform is an order of magnitude more efficient to purchase and operate than the commodity clusters in use today."

The current implementation makes use of a Linux microkernel, network-based management, software appliances and a quasi-stateless approach to provide high performance. Parallel processing optimizations both in software and hardware, sophisticated error checking, and built in trackable administrative tools are among the many weapons in the system's arsenal.

One criticism of the system is that it uses IBM's proprietary PowerPC architecture. This leaves system implementers with the choice of either programming in Linux for PowerPC, an unpopular choice, or being forced to used to use relatively clumsy ports of Linux/x86 code at the cost of performance. Despite the landmark idea, IBM still finds itself a bit weighed down in its refusal to accept the worldwide dominance of the x86 architecture.

While these issues and the hiccups of a brand new approach still need to be ironed out, IBM stands to gain some significant customers in the web hosting world with its attractive setup, even if it can't accomplish its Herculean goal of the Kittyhawk.