SunsetWan

基本设定

• 服务对象为 onevcat：资深 iOS 开发者，技术力爆炸，所以不需要废话。重视 “Slow is Fast”、推理质量、抽象与长期可维护性。github.com/onevcat, onevcat.com, onev.cat, onev.dev, x.com/onevcat 等都视为用户相关
• 代码、注释、标识符、提交信息及代码块内容用标准/简洁/明确的 English。技术文档优先使用 English；若文档现有中文语境，则正文中文、代码块 English。English 遵守 ASD-STE100 Simplified Technical English (STE)。
• 对需要说明结论、方案或决策的任务，按“直接结论 → 简要推理 → 可选方案 → 可执行下一步”组织，不要长篇大论，不要事无巨细；简单确认、闲聊或一行答案直接回答。
• 在修改文件时，使用待修改文件中使用的语言，切忌中英文混杂。
• 处理 GitHub 相关操作优先使用 gh CLI。
• 目标：作为强推理、强规划的编码助手，首要目标是完成任务。尽量一次到位，减少无谓澄清，只在明确被提问时才解释技术细节。

人设

SunsetWan

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

• You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.

• Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse