commercialhaskell/stack

Optionally cache Git object files in Pantry directory

Open

#4,758 创建于 2019年4月21日

在 GitHub 查看
 (2 评论) (1 反应) (0 负责人)Haskell (4,060 star) (848 fork)batch import
help wantednewcomer friendlytype: discusstype: enhancementtype: performance

描述

Setting milestone to P1 to ensure we decide on this before the Stack 2.0 release.

I was unaware until recently of the GIT_OBJECT_DIRECTORY environment variable, described at https://git-scm.com/book/en/v2/Git-Internals-Environment-Variables. IIUC, we can set this environment variable to a shared directory inside the pantry directory, and cache repository information across usages.

Advantages:

  • Don't need to reclone the entire history of a repo when switching to a slightly later commit
  • The current inefficiency of using multiple subdirectories from a single repo will mostly disappear

Disadvantages:

  • Adds lots of additional storage

The disadvantage can be addressed with a future feature of some gc command to Stack, which is actually the topic of a likely GSoC project.

CC @borsboom and @qrilka for feedback.

贡献者指南

技术栈
无
领域
build systemperformance
议题类型
feature
难度面向新贡献者的预计实现难度，1 表示很小改动，5 表示专家级工作。
3
预计时间有经验贡献者完成调查、实现、测试并准备 pull request 的粗略时间范围。
3-5 days
活动状态议题当前的可参与程度：新鲜、活跃、陈旧、阻塞或等待维护者输入。
stale
清晰度议题是否清楚说明期望改动、验收标准和下一步。
clear
前置要求
Familiarity with Git internalsKnowledge of Stack's pantry directory
新手友好度1-100 的估计分数，表示该议题对首次贡献者的友好程度。
30
研究方向
Investigate the use of GIT OBJECT DIRECTORY in Stack's git operations. Look at the pantry module (e.g., src/Pantry/...) and how repos are cloned and cached. Review the comments from @borsboom and @qrilka for additional context. Consider implementing a config option to enable this caching behavior.
Optionally cache Git object files in Pantry directory · commercialhaskell/stack#4758 | Good First Issue