Friday, May 1, 2009
Thursday, April 2, 2009
Google's big surprise: each server has its own 12-volt battery to supply power if there's a problem with the main source of electricity. The company also revealed for the first time that since 2005, its data centers have been composed of standard shipping containers--each with 1,160 servers and a power consumption that can reach 250 kilowatts
Monday, March 23, 2009
- Operating System Support for NVM+DRAM Hybrid Main Memory (expect to see more of this over the next few years)
- Mobility Changes Everything in Low-Power Wireless Sensornets
- FAWNdamentally Power-efficient Clusters
- perhaps: Peloton: Coordinated Resource Management for Sensor Networks (sensor "resources" almost always include power)
- perhaps: Augmented Smart Phone Applications Through Clone Cloud Execution (title sounds similar to the Kimberly paper we read)
Friday, March 6, 2009
- IBM's Millipede uses a MEMS array of probes (much like the magnetic MEMS arrays we talked about), but these probes heat and are used to physically deform the surface of a piece of acrylic glass.
- Norsam's HD-Rosetta project etches data into a nickel plate, which can then be read either optically or with an electron microscope. The product is based upon research from Los Alamos National Lab. They claim that HD-Rosetta can store 23-400 gigabits / sq in.
Thursday, February 19, 2009
Following the discussions in class yesterday, I thought this would be an appropriate optional reading for those interested in knowing about trust establishment mechanisms in ISR.
Rapid Trust Establishment for Pervasive Personal Computing
Ajay Surie, Adrian Perrig, Mahadev Satyanarayanan and David J. Farber
Wednesday, February 18, 2009
Wednesday, February 11, 2009
While the topic of the course isn't security, the weakness of many RFID systems is a direct consequence of extremely-low-power operation: to avoid the need to have expensive and power-hungry computational capabilities on the RFID chips, many designs use a passive RFID that only sends a single value, instead of being able to participate in a cryptographic protocol. The results are predictable when they're used in scenarios where reading the chips is possible. Even some active RFID systems take shortcuts that leave them vulnerable to brute-force attacks (such as using 40-bit keys to reduce computation time and power).
Tuesday, February 10, 2009
In the "using computers to save power elsewhere" arena, Google.org has introduced PowerMeter for their employees.
Friday, January 30, 2009
(This correction provided courtesy of the hawk-eyed Charlie Garrod. Thanks, Charlie!)
Monday, January 26, 2009
According to a Sun press release, they've completed the largest datacenter consolidation project in the company's history -- which they expect to save $1M in electricity costs, and 11,000 metric tons of CO2 per year. More details in the linked article, but the datacenter uses flywheel-based UPSes, a high-end Liebert XD cooling system that can dynamically allocate the amount of cooling based on demand. (Note the little air hoods over each rack.)
The major focus seems to be on space and cooling efficiency, estimating a PUE of about 1.38. (For every 1 W of computing power, 1.38 W of power enters the datacenter.) For interesting comparison, Google claims a PUE of 1.21 across six datacenters, with one running at 1.13. It's quite likely that some of those datacenters use evaporative cooling in friendly environments, etc.
Saturday, January 24, 2009
Thursday, January 22, 2009
Tuesday, January 20, 2009
The second annual study found that data center managers are caught between two conflicting goals – more demanding user expectations and higher levels of performance, yet reducing costs remain the primary objective for the data center. The report also found that data center staffing remains problematic, servers and storage continue to be underutilized and disaster recovery plans are out of date. Finally, the respondents indicated that while they are pursuing green data center initiatives, they are doing so primarily based on cost benefits.And notes that they're attempting to do so using familiar-sounding tools:
The major server-related initiatives include server consolidation (80 percent) and server virtualization (77 percent).
Or see the full PDF version of the 2008 State of the Data Center report (pdf)
The second article talks about the C1E (extended HLT) state, (Page 6) which is like normal C1 but also turns voltage down to the lowest level. This type of sleep state may address some of the issues of using idle states in the first two papers we read this semester.
“Our vision is, how do we virtualize the entire data center?” Ms. Warrior said. “It is not about a single product. We will have a series of products that enable us to make that transition.”