从 ClearCase 迁移到 SVN 的最佳策略是什么? [英] What is the best strategy when migrating from ClearCase to SVN?

问题描述

我们正在考虑从 ClearCase 迁移到 Subversion.该项目已经存在了一段时间(7 年)，我们积极支持三个主要"版本(分支)，以及旧版本中的一些偶尔修复.该项目相当大 - 大约 200 万行 java 代码.

We are considering moving from ClearCase to Subversion. The project has been there for a while (7 years) and there are three "major" versions (branches) that we actively support, plus some occasional fixes in older releases. The project is fairly large - around 2 mln lines of java code.

我很好奇是否有人做过类似的迁移.

I am curious if there is someone that has done similar migration.

• SVN 能处理这么大的项目吗?
• 迁移所有历史版本/分支是否有意义?有哪些工具可以选择性地做到这一点?
• 这样一个项目的迁移过程需要多长时间?在迁移过程中，什么是有效的工作方式?

推荐答案

由于进行了几次此类迁移，我认为:

For having made several migrations of this kind, I would argue that:

• 您不需要将 ClearCase 版本的历史全部导入 SVN.大多数时候(根据我的经验)，只需要标记版本(一致应用于给定集合的所有文件的版本)，除非您确实需要细粒度的历史修订检查.

• you do not need to import all the history of the ClearCase versions into SVN. Most of the time (for my experience), only the labeled versions (the one which are applied consistently on all the files of a given set) are needed, unless you have a real need for a fine-grained history revision examen.

您需要在迁移过程中考虑重组:导入什么?留下什么?以及您是否希望 SVN 内容反映确切地存储在 ClearCase VOB 中的文件结构?有时，此类迁移是重新考虑其中一些文件组织的机会(通常通过对某些目录进行简单的重命名规则).

you need to think about reorganization during a migration: what do you import ?, what do you leave ?, and do you want the SVN content reflect exactly the structure of the files as stored in the ClearCase VOB ? Sometime, such migrations are the occasion to rethink some of those files organization (usually through simple renaming rules for certain directories).

ClearCase 2 SVN 方式的迁移速度更快，因为 SVN 以存储库为中心并提交一组文件，而 ClearCase 以文件为中心并逐个文件提交(慢得多)

the migration is quicker in the ClearCase 2 SVN way, since SVN is repository-centric and commit a set of files, while ClearCase is file-centric and commits file-by-file (much sloooower)

如果明确标识了要导入的文件集，则可以多次重复迁移过程，这意味着您可以在第一次(大)导入发生时继续在 ClearCase 中工作，然后放一个代码上的基线(UCM 标签)，并仅重新导入增量，从而有效地结束迁移过程.

if the set of files to import is clearly identified, the migration process can be repeated multiple times over, which means you can go on working within ClearCase while the first (large) import is taking place, then put a Baseline (UCM label) on your code, and re-import only the delta, effectively ending the migration process.

这篇关于从 ClearCase 迁移到 SVN 的最佳策略是什么?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！