August 2007 Archives
What makes software legacy? Two most popular answers are the age of the software, or the technology it was built upon. Looking at this question more critically, neither of these answers make any sense. For instance, some of the internet technologies are over 10 years old - does it make those legacy? Is Apache web server legacy? How about mainframes or Unix? Apparently these are not called legacy either - although each of these are quite old - way older than the latest buzz technology. How about software built using C or Perl? In fact, EJB 1.0, which is younger than, let's say, C language, is considered legacy now. So, it is neither the age of the software nor the age of the underlying technology that make software legacy.
I was thrilled to read about PlentyOfFish architecture at http://highscalability.com today. What impressed me most was the fact that an incredible amount of scalability was achieved completely ignoring a number of design qualities that web frameworks try to provide via layers of abstractions. This architecture just reinforces the idea that complex problems can be solved without complex abstractions.
Early this year I have blogged about the problems related to portlets using Ajax to update their UI from the client side, and my attempts at addressing those. See here and here. As I mentioned in those posts, I also tried to make the model a part of the JSR-286 API. Here is an update of where things stand now.
Recently I came across an article at InfoQ that talks about using Using ETags to Reduce Bandwith & Workload with Spring & Hibernate. Unfortunately, the implementation suggested in this article is such that validating the
ETag takes as much time (if not more) as generating the resource itself. This is an example of a premature and incorrect optimization. This article barely scratched the surface of the problem with computing caching headers (both expiry related and invalidation related) for dynamic resources.
Last week I came back from a week-long cycling trip in and around Glacier National Park and Waterton Lakes National Park. This trip was organized by Cycle America, and about 85 cyclists joined this trip, starting from Whitefish (MT) on July 21st, and ending at the same place on July 27th. We rode about 400 miles over six riding days, and climbed about 17,000 ft. Here is my trip report.