Entropy Coding and File Compression: Distinctions, Common Methods, and the Role of Local Continuity
从信息熵、概率模型和完整压缩流水线出发，讲清 Huffman、算术编码、Range Coding、ANS、Golomb/Rice，以及 RLE、LZ、BWT、预测、变换和量化等方法。
Notes & essays
Writing.
60 entriesOn technology, learning, and ideas worth keeping.
Agentic RAG Explained: Turning Retrieval into a Planning and Reflection Loop
A practical guide to Agentic RAG: how it differs from traditional RAG, how the control loop works, common architectures, implementation patterns, …
Object, File, and Block Storage: How to Choose in the Cloud
A practical explanation of object, file, and block storage through addressing, metadata, I/O paths, consistency, redundancy, and workload fit.
The Complete MCP Guide: Architecture, Remote Call Flow, and Building Your Own Server
Understand MCP hosts, clients, servers, and primitives; trace a remote call end to end; then build, deploy, secure, and connect a Python MCP server to …
FastGPT in Depth: RAG, Workflows, and Self-Hosting
A practical guide to FastGPT architecture, RAG retrieval, visual workflows, self-hosting, APIs, production tuning, and project fit.
From Keyword Matching to Vector Retrieval: Three Ways to Search
A practical comparison of keyword matching, fuzzy search, vector retrieval, and RAG, with diagrams and classic application patterns.
互联网架构演进：从单机到云原生，一篇讲清楚
基于视频《互联网架构就这？1个故事讲清楚》整理并扩展，按业务压力、技术解法和架构代价梳理互联网系统从单机到微服务、云原生的完整演进路径。
Those Mystery Processes Finally Make Sense: OpenEnd
A screenshot-led introduction to OpenEnd, a Windows tool for understanding occupied ports, local processes, resource usage, and leftover development …
KV Cache 深入理解：为什么只存 K/V，不存 Q
从 Transformer 自注意力、Prefill/Decode、缓存张量形状、显存公式到工程优化，系统讲清楚 KV Cache 的工作方式，以及为什么旧 Query 没有缓存价值。
Common Image Formats Explained: JPG, PNG, GIF, WebP, AVIF, SVG, and More
A practical comparison of common image formats by compression, transparency, animation, quality, compatibility, and use cases.