Links for Monday, January 3, 2011

• John Wiegley: Git From the Bottom Up – “In my pursuit to understand Git, it’s been helpful for me to understand it from the bottom up—rather than look at it only in terms of its high-level commands. And since Git is so beautifully simple when viewed this way, I thought others might be interested to read what I’ve found, and perhaps avoid the pain I went through finding it.“
• Sergey Melnik: Dremel: Interactive Analysis of WebScale Datasets – “Dremel is a scalable, interactive ad-hoc query system for analysis of read-only nested data. By combining multi-level execution trees and columnar data layout, it is capable of running aggregation queries over trillion-row tables in seconds. The system scales to thousands of CPUs and petabytes of data, and has thousands of users at Google. In this paper, we describe the architecture and implementation of Dremel, and explain how it complements MapReduce-based computing.“