Right floating image in GitHub’s README.md

Summary This incident examines why right‑floating images in GitHub README.md behave unpredictably, especially when placed near Markdown headings. GitHub’s Markdown renderer mixes Markdown and sanitized HTML, which leads to layout collisions such as header underline borders overlapping floated images. Root Cause The underlying issue is that GitHub’s Markdown engine (CommonMark + HTML sanitization) does not … Read more

Neural Networks with weight plus input instead of multiplication?

Summary This postmortem analyzes an experimental neural‑network design that replaces the standard weighted multiplication (w_i x_i) with a weight–input addition (w_i + x_i). While the idea appears computationally attractive, the resulting model underperforms and introduces structural issues that make deeper architectures difficult to train—even with autograd. Root Cause The core issue is that addition destroys … Read more

How to get the same domain name working on my internal LAN and also externally via tailscale?

Summary This postmortem analyzes why a single domain name failed to resolve consistently on both a local LAN and over Tailscale. The core issue stemmed from DNS split‑horizon behavior and the assumption that a public DNS record could simultaneously serve internal and Tailscale clients without additional configuration. Root Cause The failure occurred because public DNS … Read more

Why doesn’t [[msvc::no_unique_address]] work like [[no_unique_address]] here?

Summary A class hierarchy using [[msvc::no_unique_address]] fails to compile on MSVC when multiple empty members with this attribute appear across base and derived classes. The behavior differs from standard [[no_unique_address]], leading to confusion. The failure is intentional, rooted in MSVC’s ABI rules and its more restrictive interpretation of empty-base and empty-member optimizations. Root Cause MSVC’s … Read more

Is there a way to get the current track index in libvlc?

Summary Issue: Determining the current track index in a MediaListPlayer using python-vlc is non-trivial due to limitations in libvlc_media_list_index_of_item(). Root Cause Lack of Direct API: python-vlc does not provide a direct method to retrieve the current track index from a MediaListPlayer. Ambiguity in libvlc_media_list_index_of_item(): This function returns the first matched position, which is unreliable if … Read more

trying to do recommended for you feature with ML

Summary This incident documents a failed attempt to build a “Recommended for You” movie feature using machine‑learning techniques without first establishing a stable baseline, clear evaluation metrics, or a reproducible experimentation workflow. The system produced inconsistent recommendations, poor ranking quality, and unpredictable behavior once deployed behind a Node.js API. Root Cause The primary root cause … Read more

How to resolve memory imbalance in PolarDB PG after enabling IMCI?

Summary This incident analyzes memory imbalance in PolarDB PostgreSQL with IMCI enabled, where the RW node experiences significantly higher memory pressure than RO nodes due to row‑to‑columnar conversion overhead. The imbalance leads to RW OOM events during peak load, impacting service stability and query latency. Root Cause The core issue arises from IMCI’s row‑to‑columnar conversion, … Read more

How do parameter sets resolving positional parameters in Powershell?

Summary This postmortem analyzes why a seemingly valid PowerShell parameter‑set design fails to resolve when positional parameters overlap across sets. The failure stems from PowerShell’s parameter binder attempting to match all possible parameter sets simultaneously, leading to ambiguous interpretations even when a human believes the intent is obvious. Root Cause The root cause is parameter‑set … Read more