Better Software Development with Replay Debugging

Wednesday, September 14, 2011

Goodbye, Replay Debugging…

Note: I'm speaking for myself on this blog, not my employer.

You may have noticed that there hasn't been much action at recently. Well, there's a reason. As of VMware Workstation 8 (released September 14, 2011), replay debugging no longer exists. Both the Windows and Linux flavors of replay debugging are no more. But I should point out that live debugging, assisted via the VMware Visual Studio add-on, continues to work as it always has.

The Workstation management team has decided to focus on features that reach a wider audience, including developers. After the Workstation 7.1 release, we identified the next set of improvements that needed to be made to Replay Debugging to evolve it into the system we wanted it to be. We wanted to include multi-processor VM support, support additional high-level languages, support debugging of system code, and continue to improve performance and usability. Our effort estimate turned out to be rather significant (not surprising given the epic scope of the problem that we tackled in the first place). The Workstation management team concluded that not enough people had demonstrated the need or invested the time necessary to configure and use the feature, so they decided to dedicate our engineers to features that would be used by more developers and other customers. I'm disappointed, but I understand and respect their decision.

I'm grateful for the opportunity given to our team to build our replay debugging system, and I'm proud of what we've produced. We have some truly heroic developers on our team that helped us achieve what at first blush appeared to be impossible. It has been extremely gratifying working with customers who have derived benefit from our little project. And it's been great hearing your stories and feedback and successes.

To those of you who have come to rely on replay debugging, I offer my apologies. But I think we've proven the practicality and utility of replay debugging systems, and I suspect others will build similar great products to help you solve your most challenging development puzzles.

Happy hacking.