I’ve always learned how Linux’s memory management works in bits and pieces, never in a formal or focused way. Recently at work, I had to debug some OOM kills, and I felt like I struggled a lot because I didn’t have a solid foundation in Linux memory management. This guide distills what I’ve learned after doing some research. Virtual Memory Every process has its own virtual address space. The OS and CPU translate virtual addresses into physical addresses, allowing memory to be backed by physical RAM and by disk through mechanisms such as swap. Read more

Many Kubernetes resources show conditions in their status. You can quickly view them with kubectl describe. $ kubectl describe pod/nginx ... Conditions: Type Status PodReadyToStartContainers True Initialized True Ready True ContainersReady True PodScheduled True ... Conditions appear as a list. Each condition type represents a separate observation about the resource, not a step in one shared state machine. You generally cannot summarize a resource by assuming all conditions should be True; some condition types use False as the healthy value. Read more

Opencode is a terminal-based AI assistant that lets you chat with multiple models from a single interface, without switching to applications like Claude Code, Codex, gemini cli, or managing multiple subscriptions. Read more

Go’s log/slog package can automatically print keys from the passed context using slog.InfoContext. Read more

Demonstrates using the Kubernetes Downward API to inject resource-derived env vars like GOMAXPROCS without hitting the API server. Read more

Introduces journald RateLimitBurst/Interval, why throttling noisy logs matters, and how to scope limits per unit. Read more

Covers chapter 4 topics: static vs dynamic instrumentation, profiling vs tracing, and expected sampling overheads. Read more

Summarizes chapter 3 Q&A on OS terminology, process/thread differences, memory management, and kernel duties. Read more

Answers Systems Performance chapter 2 exercises, clarifying metrics like IOPS, utilization, and troubleshooting methodologies. Read more

Defines MTU fundamentals, fragmentation rules for IPv4/IPv6, and how Path MTU Discovery finds the safe packet size. Read more