CVS - Concurrent Versions System
CVS（Concurrent Versions System，并发版本系统）在软件开发早期曾被广泛用作版本控制系统，但后来由于多种原因而过时，并被 SVN（Subversion）等更新的系统所取代：
CVS (Concurrent Versions System) was widely used as a version control system in the early days of software development, but it became obsolete and was largely replaced by newer systems like SVN (Subversion) for several reasons:
1. 改进的 SVN 功能集
- 原子提交： 在 CVS 中，如果出现错误，提交可能只适用于某些文件，从而导致部分提交。SVN 引入了原子提交，确保要么提交所有更改，要么不提交任何更改，从而降低了不一致的风险。
- 高效的目录处理： CVS 主要基于文件，在处理目录方面很吃力。SVN 将目录视为一等公民，允许对整个目录进行重命名、移动和版本管理。
- 更好的元数据管理： SVN 拥有更强大的元数据处理方式（如跟踪文件移动或重命名），而 CVS 无法有效跟踪此类更改。
1. Improved Feature Set in SVN
- Atomic Commits: In CVS, a commit might apply only to certain files if an error occurs, leading to partial commits. SVN introduced atomic commits, ensuring that either all changes are committed or none are, reducing the risk of inconsistencies.
- Efficient Directory Handling: CVS was primarily file-based and struggled with handling directories. SVN treats directories as first-class citizens, allowing renaming, moving, and versioning of entire directories.
- Better Metadata Management: SVN has a more robust way of handling metadata (like tracking file moves or renames), whereas CVS does not effectively track such changes.
2. 性能和可扩展性
- CVS 的性能问题：随着项目规模的扩大，CVS 的性能也会随之下降。SVN 在处理大型版本库方面进行了改进，为大型团队和项目提供了更好的性能。
- 分支与合并： CVS 的分支和合并模式较弱，经常导致复杂且容易出错的合并。SVN 提供了更强大的分支和合并功能，使维护多个开发分支并在它们之间合并变更变得更容易。
2. Performance and Scalability
- Performance Issues in CVS: CVS's performance degrades over time as projects grow in size. SVN introduced improvements in handling large repositories, providing better performance for larger teams and projects.
- Branching and Merging: CVS had a weak model for branching and merging, often leading to complex and error-prone merges. SVN offers more powerful branching and merging capabilities, making it easier to maintain multiple development branches and merge changes between them.
3. 更好地支持二进制文件
- CVS 在处理二进制文件方面效率不高，因为它针对文本文件进行了优化。SVN 的设计能更有效地管理文本和二进制文件，因此对于包含图片、编译二进制文件或其他非文本资产的项目来说，它是一个更好的选择。
3. Better Support for Binary Files
- CVS wasn't efficient at handling binary files because it was optimized for text-based files. SVN was designed to manage both text and binary files more effectively, making it a better choice for projects that include things like images, compiled binaries, or other non-text assets.
4. 更易于配置和使用
- 与 CVS 相比，SVN 的设计对用户更友好，设置更简单，需要人工干预的怪癖也更少。例如，SVN 的版本库结构更直观，工具提供的反馈和错误信息也更好。
4. Easier Configuration and Usability
- SVN's design is more user-friendly compared to CVS, with easier setup and fewer quirks that needed manual intervention. For example, the repository structure in SVN is more intuitive, and the tool provides better feedback and error messages.
5. 更广泛地采用 Subversion
- 随着时间的推移，Subversion (SVN) 因其增强的功能集而被更多的团队和组织所采用，因此 CVS 的支持和更新也越来越少。SVN 的设计也更符合现代软件开发实践。
5. Wider Adoption of Subversion
- Over time, Subversion (SVN) was adopted by more teams and organizations due to its enhanced feature set, and as a result, CVS saw less support and fewer updates. SVN’s design also better aligned with modern software development practices.
6. 社区与开发
- 在 SVN 不断发展的同时，CVS 的发展却停滞不前。随着时间的推移，SVN 获得了更多的工具、集成和社区支持，从而将 CVS 逐步淘汰。
6. Community and Development
- CVS development stagnated while SVN continued to evolve. This led to more tools, integrations, and community support for SVN over time, pushing CVS into obsolescence.
尽管 SVN 本身已基本被 Git 等分布式版本控制系统 (DVCS) 所取代，但与 CVS 相比，它还是向前迈出了关键的一步。
Although SVN itself has been largely replaced by distributed version control systems (DVCS) like Git, it was a crucial step forward from CVS.