Blog
Technical notes and the story of learning with AI. · 中文版 →
When sleep infinity Is PID 1: How Zombies Stall docker exec on cgroup freeze
2026-07-23 — A long-lived sleep infinity lab container started failing docker exec with waiting for the cgroup to freeze. It looked like resource exhaustion. It was unreaped zombies plus a freezer stuck in FREEZING.
Access macOS via Public IPv6 SSH from Mobile: Full Troubleshooting Log
2026-07-22 — The ONT only delegates IPv6 to whatever's directly attached, and a Ruijie thin AP can't act as a gateway at all — promoting an edge TP-LINK to primary router (dial-up + PD) got around double NAT so Termius over cellular can SSH straight into a Mac.
Demystifying C++: From C++23 Recursive Lambdas to Type Erasure
2026-07-18 — From C++23's explicit object parameter and lambda-to-closure-class lowering to std::function's type erasure and devirtualization.
Unmasking Docker: From Linux Syscalls to Hardware Virtualization
2026-07-17 — Containers aren't lightweight VMs — from namespaces and cgroups to shared page cache and WSL2's hardware virtualization, all the way down to the kernel.