The ARM onslaught attack on the datacenter proceeds apace, as ARM server vendor Calxeda (formerly Smooth Stone) announces that it's teaming up with Canonical and nine other software vendors to form a "Trailblazer Initiative" aimed at creating a full-blown ARM server ecosystem.

Canonical's role in the effort arises from the fact that Calxeda has selected Ubuntu as the official OS for its 120-node, 2U server box. Each of the Calxeda server nodes contains a single quad-core ARM chip, a bit of memory, and some interconnect hardware that, all told, consumes about 5 watts. Calxeda can cram 120 (480 cores worth) of these into a single 2U rackmount server chassis, which makes for an incredibly dense cluster of cloud compute resources.

Calxeda's competition on the x86 side of the fence isn't just Xeon. Last year, a startup called SeaMicro also launched a similarly dense cloud server based on Intel's Atom processor. The SeaMicro box packs 512 cores worth of Atom into a 10U space. This is significantly less density than Calxeda provides, but the individual Atom cores outperform the ARM cores, so the comparison isn't quite apples-to-apples.

Both Intel and ARM and moving aggressively to position their respective low-power processors as datacenter alternatives. ARM's A15 core, codenamed Eagle, is aimed squarely at the datacenter; Intel, for its part, has been adding datacenter-friendly features to Atom (e.g., support for ECC memory) and plans to let Atom and Xeon duke it out for rack space.

At the most recent Intel investor day, one of the Intel execs made reference to the fact that, for the longest time, Intel protected Itanium from Xeon cannibalization by not adding some features to the latter. The exec then stated that Intel won't protect Xeon from Atom in this manner; Xeon will rise or fall vs. Atom based purely on customer demand.