http://blog.mountaingoatsoftware.com/differences-between-scrum-and-extreme-programming
Scrum and Extreme Programming (XP) are definitely very aligned. In fact, if you walked in on a team doing one of these processes you might have hard time quickly deciding whether you had walked in on a Scrum team or an XP team. The differences are often quite subtle, but they are important.
I think there are four main differences between Scrum and XP:
1.Scrum teams typically work in iterations (called sprints) that are from two weeks to one month long. XP teams typically work in iterations that are one or two weeks long.
2.Scrum teams do not allow changes into their sprints. Once the sprint planning meeting is completed and a commitment made to delivering a set of product backlog items, that set of items remains unchanged through the end of the sprint. XP teams are much more amenable to change within their iterations. As long as the team hasn’t started work on a particular feature, a new feature of equivalent size can be swapped into the XP team’s iteration in exchange for the unstarted feature.
3.Extreme Programming teams work in a strict priority order. Features to be developed are prioritized by the customer (Scrum’s Product Owner) and the team is required to work on them in that order. By contrast, the Scrum product owner prioritizes the product backlog but the team determines the sequence in which they will develop the backlog items. I’ve never seen a Scrum team not choose to work on the highest-priority item. And a Scrum team will very likely choose to work on the second most important. However, at some point one of the high priority items may not be a good fit for the sprint being planned—maybe a key person who should work on it will be swamped by work on higher priority items. Or maybe it makes sense to work on a slightly lower priority item (let’s say #10 on the product backlog instead of #6) because the team will be working in the code where #10 would be implemented.
4.Scrum doesn’t prescribe any engineering practices; XP does. I love the XP engineering practices, particularly things like test-driven development, the focus on automated testing, pair programming, simple design, refactoring, and so on. However, I think it’s a mistake to say to the team “you’re self-organizing, we trust you, but you must do these specific engineering practices….” This sends a mixed message to the team that causes confusion. I love the XP practices but don’t like mandating them. I want teams to discover the value on their own.
These are small and often subtle differences between Scrum and XP. However, they can have a profound impact on the team. My typical advice to teams is “start with Scrum and then invent your own version of XP.” The XP practices are wonderful but they work best and teams commit to them the most stridently if they discover them themselves rather than having them mandated. I help teams do this in my coaching by asking questions like, “Would this bug have happened if we’d been doing test-driven development?” and “Would we have made that mistake if we were pairing?”
I find true XP to be a small target off in the distance. If a team can aim at that and hit the bull’s eye, wonderful. If not, however, they are likely hacking (e.g., refactoring without any automated testing or TDD). Scrum is a big bull’s eye that on its own brings big improvements simply through the additional focus and the timeboxed iterations. That’s a good starting point for then adding the XP practices.
分享到:
相关推荐
Differences between C++ and C# 可以看看。
Differences between EEWB and BDT
however, there are some significant differences between the capabilities of Silverlight and WPF, as well as important differences in the programming features of the two technologies. There are ...
Talk Show Differences Between China and America from the Perspective of the Form and Express.zip
The Differences Between Chinese and American Cultures from the Perspective of Politeness Utterances.zip
What are the differences between least-squares and Kalman filtering
Differences Between S32K11x and S32K142,11x系列与K142的不同
state 50 differences between marketing and sales
英语和汉语的区别
飞思卡尔为处理器IMX51与IMX53的区别
Cultural Differences in Diets Between China and the West.zip
Employment-related differences between male and female school psychologists Psychulony in Ihe Schools Yollrme 31. July /994 EMPLOYMENT-RELATED DIFFERENCES BETWEEN MALE AND FEMALE SCHOOL ...
Differences between urban and rural school psychology: Training implications P \ i i h o l o ~ i in rhr Srhvolr I Y X I . l R . 191-196 DIFFERENCES BETWEEN URBAN AND RURAL SCHOOL PSYCHOLOGY: ...
Evolutionary Programming and Evolution Strategies Similarities and Differences
Contributions from the foremost international researchers and practitioners in the GP arena examine the similarities and differences between theoretical and empirical results on real-world problems....
SQL相关资料
Contributions from the foremost international researchers and practitioners in the GP arena examine the similarities and differences between theoretical and empirical results on real-world problems....
Exercise 2.1: What are the differences between int, long, long long, and short? Between an unsigned and a signed type? Between a float and a double? Exercise 2.2: To calculate a mortgage payment, what...
Diagnostic differences between educationally handicapped and learning disabled students Pr~.rhulugv in the Schuul.r PPVT and MSCA with Autistic Children 469 1980. 17. 469-473 SCHOPLER, E. ...
Contributions from the foremost international researchers and practitioners in the GP arena examine the similarities and differences between theoretical and empirical results on real-world problems....