Øredev 2010 - JVM Bytecode for Dummies. CoffeeScript. GFS the Google File System in 199 Lines of Python. GFS, the Google File System, sits as the backbone of the entire Google infrastructure. However, for many it is a mystery, especially for those lucky enough to be more acquainted with high-level python code than low-level C operating system sources.
But have no fear, we shall break through the veil and describe an implementation of GFS in 199 lines of python. Naturally, you may want to read about the theory and design of GFS in the original Google Research GFS paper. But we will aim to give the core concepts, with real working python code, in this article. Complete runnable python 2.6 source code, if you wish it, is available at the end of this post.
A brief summary of GFS is as follows. GFS consists of three components: a client, a master, and one or more chunkservers. The client class is the only user-visible portion of the GFS library. The master class simulates a GFS master server. The chunkserver class is the smallest in this project. . $ python gfs.py Writing... Keeping Zip. I still have not decided whether I like the Zip file format... About two months ago, I stumbled upon an interesting problem. I was constructing a forensic timeline for some files on a hard drive (investigating a compromised host) and noticed that different unzip programs were showing me different dates.
Moreover, if I unzipped the file contents, the unzip programs populated different timestamps. Huh? The first part of the problem was pretty easy. That was when I decided to dig deeper into zip files. Zip Structure The entire zip format uses little endian for storing values. As far as I can tell, there are really only four block types: File entry, End of file entry, Central directory entry, and End of central directory. The end of the zip file holds the end of central directory (denoted by the 0x06054b50 tag, located 20 bytes before the end of file). At the beginning of the zip file are the important parts. The Minimal Time Some bit patterns will never happen. Finding Records Without Limits. New York Times Looks for Answers in Data: Tech News « High up on the 28th floor of the New York Times, a pair of researchers have been poring over the newspaper’s data, looking to understand the way influence plays out online.
What Mark Hansen, a UCLA statistics professor on sabbatical, and Jer Thorp, a data artist in residence at the Times, have found is that stories take on a life of their own, which can be mapped and visualized in some startlingly beautiful ways. The work, still “crazy” preliminary, shows how organizations are looking to mine their data to find ways to improve their operations. And it also shows the challenges that lay ahead in trying to turn the data into clear actions. Hansen and Thorp, who talked at a TimesOnline TimesOpen event last night, took two weeks of August data from the paper, looking at how stories were shared through the Times’ site, Bit.ly and Twitter.
While it’s still quite early, Hansen said the next steps will be to make the project handle both real-time and archived information. The Beautiful Art of Japanese Web Design – woorkup.com. Datamining. Data Mining 101: Finding Subversives with Amazon Wishlists. Vast deposits of personal information sit in databases across the internet. Terms used in phone conversations have become the grounds for federal investigation.
Reputable organizations like the Catholic Worker, Greenpeace, and the Vegan Community Project, have come under scrutiny by FBI "counterterrorism" agents. "Data mining" of all that information and communication is at the heart of the furor over the recent disclosure of government snooping. "U.S. President George W. Bush and his aides have said his executive order allowing eavesdropping without warrants was limited to monitoring international phone and e-mail communications linked to people with connections to al-Qaeda. What has not been acknowledged, according to the Times, is that NSA technicians combed large amounts of phone and Internet traffic seeking patterns pointing to terrorism suspects.
It used to be you had to get a warrant to monitor a person or a group of people. Keywords. Web Design Portfolio | Jakarta Designer | Muhamad Alief Ikhsan. What Colour are your bits? Thu 10 Jun 2004 by mskala Tags used: colour, copyright, philosophy There's a classic adventure game called Paranoia which is set in an extremely repressive Utopian futuristic world run by The Computer, who is Your Friend. Looking at a recent LawMeme posting and related discussion, it occurred to me that the concept of colour-coded security clearances in Paranoia provides a good metaphor for a lot of copyright and intellectual freedom issues, and it may illuminate why we sometimes have difficulty communicating and understanding the ideologies in these areas. An article based on this one and its follow-ups, by me, Brett Bonfield, and Mary Fran Torpey, appeared in the 15 February 2008 issue of LJ, Library Journal.
In Paranoia, everything has a colour-coded security level (from Infrared up to Ultraviolet) and everybody has a clearance on the same scale. You are not allowed to touch, or have any dealings with, anything that exceeds your clearance. Bits do not naturally have Colour. Technophilia: Protect your web searches - Lifehacker.
710960 - What Killed Waterfall Could Kill Agile.- GitHub. Ganked from unreadable scribd doc here: Robert C. Martin 20 Nov, 2010 In 1970 a software engineer named Dr. Winston W. Royce wrote a seminal paper entitled Managing the Development of Large Software Systems. This paper described the software process that Royce felt was appropriate for large-scale systems. He began the paper by setting up a straw-man process to knock down. Royce’s paper was an instant hit. There was just one problem. Though Royce railed and fought against it, the snowball was in motion. By the middle of the 1990s, the waterfall process dominated the world of software.
This attitude created a schism in the technical community. This was a great deal for the elite Architects, Designers, and Analysts! Scrum broke the waterfall apart. 1 Nowadays two weeks is more common than 30 days. Scrum suggested that the development team should decide when and if a document was necessary. XP took this even farther.