|By Kevin Bedell||
|December 13, 2004 12:00 AM EST||
Recently I had the opportunity to talk with the authors of Version Control with Subversion. In this interview, they discuss what Subversion is, migrating to Subversion, and, of course, music.
What is Subversion?
Subversion is an open source version control system. It was designed to be a compelling replacement for CVS - preserving the basic workflow and user experience of that system, but providing significant improvements over CVS's model (and its implementation).
Who hosts it and what license is it distributed under? Is the license OSI approved?
Subversion is hosted by CollabNet (www.collab.net), which also funds large parts of Subversion's development. The project calls Tigris.org - an online open source collaborative software development community - its home. Subversion is developed under CollabNet's license, which is a modified version of the Apache license (and fully compliant with the Debian Free Software Guidelines).
Are any large projects using Subversion now?
Absolutely. Subversion is currently being used by many large development teams, both open source and commercial. Some examples of large open source projects using Subversion include the folks at Samba, Zope, and Xiph. Notably, the Apache Software Foundation started using Subversion in early 2003, and started migrating projects to Subversion in earnest when Subversion reached 1.0 last February. Both Apache Geronimo and Apache SpamAssassin are using Subversion, and Apache HTTP Server is preparing to convert any day now.
What was wrong with CVS? Why was a new source control system needed?
CVS works just fine for file-based version control (as does RCS, the system atop which CVS is constructed). As it turns out, most projects typically involve more than one file, and that's when you start noticing creaks in the floors and cracks in the walls. CVS does not provide atomicity for changes across multiple files - does not, in fact, even have a notion of such a change "set." CVS does not do version changes to directory structure, such as file and subdirectory additions or removals, or items that are renamed. It's extremely inefficient in its handling of "binary" (nontextual) files. It was never designed with networks in mind; that support was entirely an afterthought.
Fixing these problems within the constraints of the basic CVS architecture was already a nonviable solution. But when you then examine the state of CVS's source code and lack of a modular, extensible design, you come away without a shadow of doubt - it was time to begin anew.
What are some of the cool new features of Subversion?
Besides fixing most of the major problems found in CVS, Subversion has additional perks. For example, the file and directories you keep under version control can have property lists - arbitrary name/value pairs - attached to them. Subversion itself uses these lists to track stuff like the MIME type, preferred line-ending style, keyword expansion setting, executability, etc. But users can set their own properties willy-nilly, and use them for whatever they would like. The properties themselves are versioned, too.
Another neat feature involves Subversion's network connectivity. Since one of the available server options is an Apache WebDAV module, you have at your fingers all the functionality and extensibility that Apache offers, plus a fair degree of WebDAV interoperability, all for free. This means you can refer directly to a Subversion repository URL when trying to get your grandmother to view the latest version of something you keep under version control, and Apache will just serve up that document like any other Web resource.
Readers should check out the Subversion Web site (http://subversion.tigris.org) for news about the latest and greatest coolness flowing from that community.
What steps should I take to migrate from CVS to Subversion?
Perhaps the biggest decision involved in a migration like this is what to do with all the versioned data you currently have stored in CVS repositories. For some folks, the answer is to just leave that data in CVS, take a "top-skim" of the latest versions of all the files in that repository, and import them into a new Subversion repository. But for those who desire a full migration of their CVS history, the cvs2svn tool (http://cvs2svn.tigris.org/) is the way to go.
Along the way you'll hit other decision-making points (a beautiful side effect of Subversion's modular design). For example, you'll have to choose between a pair of back-end storage mechanisms and decide which of a handful of network access routes you'd like to use with your repository.
Of course, you'll need a copy of Version Control with Subversion by your side! There is a section entitled "How to Read This Book" in the preface, which is perhaps the best launching point for the various audiences of the book, as well as a quick-start guide at the end of Chapter 1 aimed at helping folks get set up with enough of Subversion to start experimenting with it.
So you three helped write Subversion? Why did you get involved?
Ben: In 2000, I was still working as a Unix sysadmin, pining for a chance to code again. My buddy Karl Fogel and I had started writing some free software in our spare time, but then he got the call from CollabNet. Karl wasn't willing to move to San Francisco, so he got permission to pull together a Chicago-area team. Getting paid to write open source software (with your friends) is an almost unbelievable dream come true, so I jumped at the opportunity. Karl and I still joke that we originally thought it would take six months - not four years - to finish a 1.0 product!
Fitz: Back in 2000, Karl Fogel called me up to tell me that Brian Behlendorf had hired him at CollabNet to start work on the successor to CVS. I was very excited about the idea of Subversion (which was actually called "Inversion" back then) and started following Subversion's development and helped out here and there as time permitted. Eventually, I joined CollabNet full-time where I work with Karl, Mike, and Ben on Subversion and other various mind-control, um, I mean version-control related projects. I would like to state for the record that I do not and have never played the banjo.
Mike: Ben made me do it! Seriously, working on Subversion afforded me the opportunity to help design and implement a piece of software that promised to alleviate frustrations I was running into daily using CVS and Visual Source Safe. As my first foray into the open source culture, it gave me a chance to experience firsthand what all the buzz was about. When Ben and Karl called me up to say that they were now a year into their six-month project and needed a hand, I went to work for CollabNet.
In your office, musical instruments outnumber computers two-to-one. Are you really programmers?
No, we're musicians.
Although we're programmers by day, we've all got musical interests to some degree or other.
Fitz: Ben is an amazing musician who plays piano, guitar, and banjo, not to mention the fact that he's quite the barbershop singer too. When he's not programming, writing books, answering e-mail, or helping out Subversion users on IRC, Ben composes musicals and does sound design for theater with his collaborator, Andre Pluess. Quite frankly, I don't think he sleeps. Much to Ben's chagrin, floating around in my head are a handful of songs that he and Andre have written.
Ben: Mike is the "rocker" in our office. He's got a sweet PRS electric at home, but that doesn't prevent him from playing the same songs and progressive-rock licks on his acoustic guitar at the office. Mike plays in a very talented, very tight band called Autumn War. But he also writes and records a lot of his own thoughtful songs in his home studio. Call his cellphone sometime and listen to the outgoing message; it's hilarious. Though Mike's incessant desk drumming sometimes makes Fitz want to jump out the window.
Mike: Fitz grew up in the deep south. So while he claims the high tenor line during office barbershop quartet time (between morning snack and recess), his blues guitar licks are low-down, gritty goodness. In addition, he's the office DJ. He's got more muscle in his "iPod thumb" than the average hacker has on his whole body, and he has a truckload of diverse music to boot.
About Ben Collins-Sussman
Ben Collins-Sussman has been a sysadmin and programmer for 10 years, and is one of the original designers and authors of Subversion. He currently works for CollabNet as a Subversion developer and community leader. When away from his computer, he moonlights as a musical theater composer at theaters around the city of Chicago. He lives with his lovely wife, three cats, and a house full of computer and music gizmos.
About Brian W. Fitzpatrick
Brian W. Fitzpatrick is a member of the Apache Software Foundation and currently works for CollabNet. He has been involved with Subversion in one way or another since its inception in early 2000. Originally from New Orleans, Brian moved to Chicago to attend Loyola University where he received a degree in Latin and Greek.
About C. Michael Pilato
C. Michael Pilato (Mike) is a core Subversion developer, and a leader in the Subversion community. He is currently employed by CollabNet, where he spends his days (and many nights) improving Subversion and other tools with which it integrates. A husband and father, this North Carolina native also enjoys composing and performing music, freelance graphic design work, hiking, and spending quality time with his family. Mike has a degree in computer science and mathematics from the University of North Carolina at Charlotte.
Software AG helps organizations transform into Digital Enterprises, so they can differentiate from competitors and better engage customers, partners and employees. Using the Software AG Suite, companies can close the gap between business and IT to create digital systems of differentiation that drive front-line agility. We offer four on-ramps to the Digital Enterprise: alignment through collaborative process analysis; transformation through portfolio management; agility through process automation and integration; and visibility through intelligent business operations and big data.
Sep. 30, 2014 10:30 AM EDT Reads: 1,220
There will be 50 billion Internet connected devices by 2020. Today, every manufacturer has a propriety protocol and an app. How do we securely integrate these "things" into our lives and businesses in a way that we can easily control and manage? Even better, how do we integrate these "things" so that they control and manage each other so our lives become more convenient or our businesses become more profitable and/or safe? We have heard that the best interface is no interface. In his session at Internet of @ThingsExpo, Chris Matthieu, Co-Founder & CTO at Octoblu, Inc., will discuss how these devices generate enough data to learn our behaviors and simplify/improve our lives. What if we could connect everything to everything? I'm not only talking about connecting things to things but also systems, cloud services, and people. Add in a little machine learning and artificial intelligence and now we have something interesting...
Sep. 29, 2014 06:45 AM EDT Reads: 1,799
Last week, while in San Francisco, I used the Uber app and service four times. All four experiences were great, although one of the drivers stopped for 30 seconds and then left as I was walking up to the car. He must have realized I was a blogger. None the less, the next car was just a minute away and I suffered no pain. In this article, my colleague, Ved Sen, Global Head, Advisory Services Social, Mobile and Sensors at Cognizant shares his experiences and insights.
Sep. 28, 2014 09:45 AM EDT Reads: 1,480
We are reaching the end of the beginning with WebRTC and real systems using this technology have begun to appear. One challenge that faces every WebRTC deployment (in some form or another) is identity management. For example, if you have an existing service – possibly built on a variety of different PaaS/SaaS offerings – and you want to add real-time communications you are faced with a challenge relating to user management, authentication, authorization, and validation. Service providers will want to use their existing identities, but these will have credentials already that are (hopefully) irreversibly encoded. In his session at Internet of @ThingsExpo, Peter Dunkley, Technical Director at Acision, will look at how this identity problem can be solved and discuss ways to use existing web identities for real-time communication.
Sep. 27, 2014 11:30 PM EDT Reads: 1,827
Can call centers hang up the phones for good? Intuitive Solutions did. WebRTC enabled this contact center provider to eliminate antiquated telephony and desktop phone infrastructure with a pure web-based solution, allowing them to expand beyond brick-and-mortar confines to a home-based agent model. It also ensured scalability and better service for customers, including MUY! Companies, one of the country's largest franchise restaurant companies with 232 Pizza Hut locations. This is one example of WebRTC adoption today, but the potential is limitless when powered by IoT. Attendees will learn real-world benefits of WebRTC and explore future possibilities, as WebRTC and IoT intersect to improve customer service.
Sep. 27, 2014 10:30 PM EDT Reads: 1,758
From telemedicine to smart cars, digital homes and industrial monitoring, the explosive growth of IoT has created exciting new business opportunities for real time calls and messaging. In his session at Internet of @ThingsExpo, Ivelin Ivanov, CEO and Co-Founder of Telestax, will share some of the new revenue sources that IoT created for Restcomm – the open source telephony platform from Telestax. Ivelin Ivanov is a technology entrepreneur who founded Mobicents, an Open Source VoIP Platform, to help create, deploy, and manage applications integrating voice, video and data. He is the co-founder of TeleStax, an Open Source Cloud Communications company that helps the shift from legacy IN/SS7 telco networks to IP-based cloud comms. An early investor in multiple start-ups, he still finds time to code for his companies and contribute to open source projects.
Sep. 27, 2014 10:30 PM EDT Reads: 2,232
The Internet of Things (IoT) promises to create new business models as significant as those that were inspired by the Internet and the smartphone 20 and 10 years ago. What business, social and practical implications will this phenomenon bring? That's the subject of "Monetizing the Internet of Things: Perspectives from the Front Lines," an e-book released today and available free of charge from Aria Systems, the leading innovator in recurring revenue management.
Sep. 27, 2014 09:45 PM EDT Reads: 2,413
The Internet of Things will put IT to its ultimate test by creating infinite new opportunities to digitize products and services, generate and analyze new data to improve customer satisfaction, and discover new ways to gain a competitive advantage across nearly every industry. In order to help corporate business units to capitalize on the rapidly evolving IoT opportunities, IT must stand up to a new set of challenges.
Sep. 27, 2014 08:45 PM EDT Reads: 2,299
There’s Big Data, then there’s really Big Data from the Internet of Things. IoT is evolving to include many data possibilities like new types of event, log and network data. The volumes are enormous, generating tens of billions of logs per day, which raise data challenges. Early IoT deployments are relying heavily on both the cloud and managed service providers to navigate these challenges. In her session at 6th Big Data Expo®, Hannah Smalltree, Director at Treasure Data, to discuss how IoT, Big Data and deployments are processing massive data volumes from wearables, utilities and other machines.
Sep. 27, 2014 01:00 PM EDT Reads: 1,989
All major researchers estimate there will be tens of billions devices – computers, smartphones, tablets, and sensors – connected to the Internet by 2020. This number will continue to grow at a rapid pace for the next several decades. With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo in Silicon Valley. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be!
Sep. 27, 2014 11:00 AM EDT Reads: 2,114
P2P RTC will impact the landscape of communications, shifting from traditional telephony style communications models to OTT (Over-The-Top) cloud assisted & PaaS (Platform as a Service) communication services. The P2P shift will impact many areas of our lives, from mobile communication, human interactive web services, RTC and telephony infrastructure, user federation, security and privacy implications, business costs, and scalability. In his session at Internet of @ThingsExpo, Erik Lagerway, Co-founder of Hookflash, will walk through the shifting landscape of traditional telephone and voice services to the modern P2P RTC era of OTT cloud assisted services.
Sep. 26, 2014 11:45 PM EDT Reads: 1,467
While great strides have been made relative to the video aspects of remote collaboration, audio technology has basically stagnated. Typically all audio is mixed to a single monaural stream and emanates from a single point, such as a speakerphone or a speaker associated with a video monitor. This leads to confusion and lack of understanding among participants especially regarding who is actually speaking. Spatial teleconferencing introduces the concept of acoustic spatial separation between conference participants in three dimensional space. This has been shown to significantly improve comprehension and conference efficiency.
Sep. 26, 2014 10:45 PM EDT Reads: 1,407
The Internet of Things is tied together with a thin strand that is known as time. Coincidentally, at the core of nearly all data analytics is a timestamp. When working with time series data there are a few core principles that everyone should consider, especially across datasets where time is the common boundary. In his session at Internet of @ThingsExpo, Jim Scott, Director of Enterprise Strategy & Architecture at MapR Technologies, will discuss single-value, geo-spatial, and log time series data. By focusing on enterprise applications and the data center, he will use OpenTSDB as an example to explain some of these concepts including when to use different storage models.
Sep. 26, 2014 07:45 PM EDT Reads: 2,245
SYS-CON Events announced today that Gridstore™, the leader in software-defined storage (SDS) purpose-built for Windows Servers and Hyper-V, will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Gridstore™ is the leader in software-defined storage purpose built for virtualization that is designed to accelerate applications in virtualized environments. Using its patented Server-Side Virtual Controller™ Technology (SVCT) to eliminate the I/O blender effect and accelerate applications Gridstore delivers vmOptimized™ Storage that self-optimizes to each application or VM across both virtual and physical environments. Leveraging a grid architecture, Gridstore delivers the first end-to-end storage QoS to ensure the most important App or VM performance is never compromised. The storage grid, that uses Gridstore’s performance optimized nodes or capacity optimized nodes, starts with as few a...
Sep. 26, 2014 06:15 PM EDT Reads: 1,587
The Transparent Cloud-computing Consortium (abbreviation: T-Cloud Consortium) will conduct research activities into changes in the computing model as a result of collaboration between "device" and "cloud" and the creation of new value and markets through organic data processing High speed and high quality networks, and dramatic improvements in computer processing capabilities, have greatly changed the nature of applications and made the storing and processing of data on the network commonplace. These technological reforms have not only changed computers and smartphones, but are also changing the data processing model for all information devices. In particular, in the area known as M2M (Machine-To-Machine), there are great expectations that information with a new type of value can be produced using a variety of devices and sensors saving/sharing data via the network and through large-scale cloud-type data processing. This consortium believes that attaching a huge number of devic...
Sep. 26, 2014 06:00 PM EDT Reads: 1,515
Innodisk is a service-driven provider of industrial embedded flash and DRAM storage products and technologies, with a focus on the enterprise, industrial, aerospace, and defense industries. Innodisk is dedicated to serving their customers and business partners. Quality is vitally important when it comes to industrial embedded flash and DRAM storage products. That’s why Innodisk manufactures all of their products in their own purpose-built memory production facility. In fact, they designed and built their production center to maximize manufacturing efficiency and guarantee the highest quality of our products.
Sep. 26, 2014 05:00 PM EDT Reads: 1,517
All major researchers estimate there will be tens of billions devices - computers, smartphones, tablets, and sensors - connected to the Internet by 2020. This number will continue to grow at a rapid pace for the next several decades. Over the summer Gartner released its much anticipated annual Hype Cycle report and the big news is that Internet of Things has now replaced Big Data as the most hyped technology. Indeed, we're hearing more and more about this fascinating new technological paradigm. Every other IT news item seems to be about IoT and its implications on the future of digital business.
Sep. 26, 2014 10:00 AM EDT Reads: 2,006
Can call centers hang up the phones for good? Intuitive Solutions did. WebRTC enabled this contact center provider to eliminate antiquated telephony and desktop phone infrastructure with a pure web-based solution, allowing them to expand beyond brick-and-mortar confines to a home-based agent model. Download Slide Deck: ▸ Here
Sep. 26, 2014 10:00 AM EDT Reads: 1,474
BSQUARE is a global leader of embedded software solutions. We enable smart connected systems at the device level and beyond that millions use every day and provide actionable data solutions for the growing Internet of Things (IoT) market. We empower our world-class customers with our products, services and solutions to achieve innovation and success. For more information, visit www.bsquare.com.
Sep. 26, 2014 09:45 AM EDT Reads: 1,365
With the iCloud scandal seemingly in its past, Apple announced new iPhones, updates to iPad and MacBook as well as news on OSX Yosemite. Although consumers will have to wait to get their hands on some of that new stuff, what they can get is the latest release of iOS 8 that Apple made available for most in-market iPhones and iPads. Originally announced at WWDC (Apple’s annual developers conference) in June, iOS 8 seems to spearhead Apple’s newfound focus upon greater integration of their products into everyday tasks, cross-platform mobility and self-monitoring. Before you update your device, here is a look at some of the new features and things you may want to consider from a mobile security perspective.
Sep. 26, 2014 09:00 AM EDT Reads: 1,351