Month: January 2012

Off-Topic: Ticket-to-Ride Pocket is Broken

Ticket to Ride is a nice real-world board game that is generally considered one of the best family and gateway games (and a decent game even for experienced gamers). We recently got it for our iPod Touches, and the weakness of the computer players quickly turned it from “I wonder if I can win this game” into “let’s shoot for the highest score possible”.

Chasing high scores is fairly typical for computer games – playing against human beings you are motivated to win, even if you win by scoring a measly 75 points… while against the computer it becomes about beating your own old scores. Unfortunately, this also turns repetitive after a while, due to some small design flaws that really should be easy to fix.

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Wind River Blog: Fault Injection with Simics

There is a new post at my Wind River blog, about how you actually do fault injection in Simics. This particular post is pretty detailed, showing the actual architecture of a fault injector in Simics, not just “yes you can do it”. It includes actual diagrams of system components and how you can insert fault injection into an existing system, so it is a bit more technical than most my Wind River blog posts that tend to be more conceptual.

Reverse History Part Three – Products

In this final part of my series on the history of reverse debugging I will look at the products that launched around the mid-2000s and that finally made reverse debugging available in a commercially packaged product and not just research prototypes. Part one of this series provided a background on the technology and part two discussed various research papers on the topic going back to the early 1970s. The first commercial product featuring reverse debugging was launched in 2003, and then there have been a steady trickle of new products up until today.

Originally published in January 2012. Post updated 2012-09-28 with a revised timeline for Lauterbach CTS. Post updated 2016-04-05 to include Mozilla RR. Post updated 2016-12-26 to add Simulics. Post updated 2017-10-08 to add Microsoft WinDbg. Post updated 2018-07-28 to add Borland Turbo Debugger.

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Reverse History Part Two – Research

This is the second post in my series on the history of reverse execution, covering various early research papers. It is clear that reverse debugging has been considered a good idea for a very long time. Sadly though, not a practical one (at the time). The idea is too obvious to be considered new. Here are some of the papers that I have found, going back before reverse debugging got started for real in actual products (around 2003) as well later on for interesting research papers that did not make it into products.  It is worth noting that products/useful software has become more common in recent times as the way that reverse debugging ideas get expressed.

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Reverse History Part One

For some reason, when I think of reverse execution and debugging, the sound track that goes through my head is a UK novelty hit from 1987, “Star Trekkin” by the Firm. It contains the memorable line “we’re only going forward ’cause we can’t find reverse“. To me, that sums up the history of reverse debugging nicely. The only reason we are not all using it every day is that practical reverse debugging has not been available until quite recently.  However, in the past ten years, I think we can say that software development has indeed found reverse.  It took a while to get there, however. This is the first of a series of blog posts that will try to cover some of the history of reverse debugging. The text turned out to be so long that I had to break it up to make each post usefully short. Part two is about research, and part three about products.
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