At a high level, Facebook is working on software that will figure out how and where to store a piece of content in the infrastructure when it ages, said Parikh. "That will mean that the copies of the data will move around over time and utilize the different pieces of infrastructure that we will have optimized for the age of content." Some of the inventions in the software layer will allow Facebook to still respond quickly but to store data more cost effectively, he said.
Cold storage will be part of Facebook's infrastructure in the next year or two, he said. Facebook plans to disclose and share the parts that it thinks are relevant through the Open Compute Project, an initiative started by Facebook to apply the open-source software collaboration model to the world of data center hardware.
Loek is Amsterdam Correspondent and covers online privacy, intellectual property, open-source and online payment issues for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to email@example.com