ME went to go check out the Google Speaker series talk : "Watts, Faults, and Other Fascinating Dirty Words Computer Architects Can No Longer Afford to Ignore" by Luiz Barroso. see here
Essentially they're flipping out about server farm energy consumption. A recent article said that data centers use something like ~15% of the total energy (kW) in the US. A more in depth survey by Berkley revealed that its more like 1.2% for 2005 and growing (according to REDHERRING)
Luiz Barroso at Google figured out that they're one of the biggest users/owners of server farms and decided to do something about it. So far, they've conducted a series of measurements on server power consumption efficiency and concluded they're not doing too well. However, Google is by no means concerned with the total amount of consumption. They are concerned about cost.
Prof. Barroso showed alarming economic projections. Namely the cost of computing being dominated by the cost energy as apposed to hardware. Naturally, the arguments he made with respect to this claim were fairly simplistic. This is ok since this was only part of the motivation for his research.
The two main points made by the speaker were as follows:
- Current Hardware behaves in ways that are extremely energy inefficient. An idle computer consumes about 40% of its peak power. Combined with the fact that most computers spend the majority of their time under less then full load, this makes for very wasteful systems
- On the other hand, given the knowledge of such usage patterns it should be possible to optimize energy usage by "overbooking" data centers. Naturally, Luiz Barroso advocated doing this cautiously.
Other reactions: The wine, beer, and cheese were a nice touch. Also, though a window on the side we saw people moving about the building on Razor Scooters. Qualifying the Google office as the coolest corporate building I've been to so far. The office space has the warehouse/trendy and they're a block away from Meatpacking. The speaker himself was very articulate, entertaining, and knowledgeable. I thought he survived the Q&A portion rather well.
Here are what I think are worthwhile points from the Q&A session afterwards:
- This seems like a 'bandaid' solution. We need a more architectural/hardware solution to this problem.
- Have they conducted experiments with server virtualization to increase loads on machines as a way to increase data center profitability? Something like VMWare or Xen. I wanted to ask this and look smart, but somebody beat me to it. This was one of the few questions that evoked a qualified response from the speaker. Prof. Barroso explained that Virtualization is nothing more then a technique for improving distributed resource utilization. This problem is fairly well studied. However, more needs to be done to fully take advantage of the energy allocated to large computing centers. The statistics presented in the talk showed that the problem was not in allocating resources when demand for them is high. The problem was in making sure that resources behaved better with respect to energy under a variety of load conditions.
- Power plants have had to deal with this problem for a while. Perhaps its worthwhile to look at work produced by power engineers. Having worked in the industry, all I can say is 'duh'
- Some pompous scholarly looking fella after reciting the Intro to Physics formula sheet concluded that the 2nd law of thermodynamics prevents total efficiency and this is all a matter of entropy. M|E thought this point cast a depressing light on the conversation.
Here is the multimedia portion of the post:
Luiz in action
Q&A with the other room. magic of Google Conference
The ubiquitous GS bag
a shot of the crowd. there was a lot of people
