A Beef with Darwin
By hendel on Oct 09, 2007
A special post indeed in this series of amorphous blogs initially inspired by CMT topics. The arrival of second generation CMT systems (the T5120 and family) is a critical evolutionary step, and a good excuse to contemplate the evolution theme.
Interpreting Darwin's evolution as the natural selection of "good" heritable traits, my beef is that bad traits must “express themselves” before they can propagate, for selection to work. If we have children in our twenties but get really sick in our seventies, it may be too late for Darwin to kick in. We could even postulate an evolution path towards species that are perfectly healthy until reproduction age, but not a day more. NiCd battery species, kind of.
It is not fair to mess up with Darwin when he isn't around to respond. We can taunt contemporary scientists instead by stating that thanks to evolution the path to longevity is through stretching the reproduction age rather than expensive medicine. Let's postpone marriage by 40 years and watch life expectancy soar! There. Taunted the health sciences community plus many other innocent bystanders, let's now run to technology topics for cover.
Darwinian world or not, computer systems don't randomly mutate traits over infinite product generations, traits are introduced deliberately and rather frequently. Before creationsists celebrate the “deliberate” aspect, let me debunk intelligent creation with a single stroke, a three-finger stroke to be precise. The infamous CTRL-ALT-DEL single handedly debunks both intelligent creation and evolution theories for computer systems. OK. I take back "single handedly"...
Products and technologies are vulnerable in their long term survival, much more so than dinosaurs were in their day. Second generations, like the T5120, are then as much about product family continuity as about constant technology improvement. Improvements that are as natural as the desire for our children to go beyond our own reach.
CMT waltzes to the cadence of Moore's Law, and T2 boxes are here less than two years after the T1 boxes. True to the spirit of the Law, T2 systems doubled the number of physical threads per socket. The thread bump has replaced the speed bump. The bump is a nice integer 2x factor, actually more than 2x, after all the T2 processor also has a faster pipeline, a larger cache with higher associativity, crypto acceleration, more memory bandwidth, a no compromises floating point unit per core, and built-in 10G networking.
The links below have plenty of data on T2 systems across different workloads, so I will stick to the networking angles for now.
High Speed Networking evolved in multiples of ten. 100 Mbps around 1995, and two 10x factors since then took us to 10Gbps. Processors doing 2x every two years would be a factor of 64, modulo sampling noise. As processors and networks evolve, the question is how to jump across these moving trains. When should the next network speed be adopted? The answer is easy if we agree on who is at the center, the host or the network.
If your religion is host centric then, for their own sake, put servers on 10G as soon as they can do more than 1G. If network infrastructure is supreme, then build its temple only with processors and servers that can do more than 10G. Copernicus isn't around either to settle centricity questions, so we built these T2 based systems to satisfy both cases.
No compromises 10G networking infrastructure on general purpose processors and general purpose COTS platforms. Specifically, with dual 10G Ethernet interfaces, no I/O bus bottlenecks, multi-threaded networking, packet classification, virtualization, water tight domain isolation, policy, asymmetrical multi-processing, packet processing pipelines, Crossbow, data plane, crypto, short packet efficiencies, all coming together to a single socket box or blade near you.
Just like a deep analysis of Darwin takes you to his actual writings, the proof points around Sun's Unified Network Platforms, consolidation,
packet processing, and the movement towards data plane on general purpose platforms may require going through white papers and kicking the tires with reference apps. Here is a start: