Pass-By-Value Parameter Causes Unintended Copy Operation Summary During optimization of a high-throughput C++ service, we identified severe performance degradation caused by unnecessary object copying in critical path code. The root issue occurred when a struct A was passed by value instead of by rvalue reference to a function spawning asynchronous operations. This resulted in: Unplanned … Read more
Summary The issue at hand is preventing unnecessary re-renders in a React application when passing callbacks to memoized child components. The problem arises because functions are re-created on every render, causing the prop reference to change, even if the props used inside the child don’t change. This leads to the child component re-rendering unnecessarily. Root … Read more
Summary When implementing jQuery UI Sortable on table rows within a Bootstrap container, the dragged row (ui-sortable-helper) horizontally overflows its responsive wrapper during drag operations. This occurs when the table’s width exceeds the viewport. Though sorting works functionally, visual overflow compromises UI integrity during drag interactions. Root Cause .table-responsive in Bootstrap uses overflow-x: auto internally, … Read more
Summary A developer faced a limitation when serializing/deserializing a custom type with boost::json::tag_invoke. Specifically, they needed to pass a logger instance into the tag_invoke function to log warnings about missing JSON fields during permissive deserialization. The issue stems from strict function signature matching required by ADL (Argument Dependent Lookup) in the boost::json namespace. You cannot … Read more
Summary The task at hand involves creating a LaTeX template for a book with a twoside header and variable content, including Japanese text and images. The goal is to achieve a specific design where the left page has a header with numbering and two right-aligned headlines, and the right page has two left-aligned headlines with … Read more
Summary The locking of NFC tags as read-only is a critical aspect of ensuring the security and integrity of the data stored on these tags. In this article, we will explore the root cause of why locking NFC tags is essential, the real-world impact of failing to do so, and provide an example of how … Read more
Summary The issue at hand is a Rust gRPC server experiencing memory growth of approximately 1GB per request, leading to an eventual Out of Memory (OOM) error. This behavior is unexpected in Rust, given its focus on memory safety and lack of garbage collection. The goal is to diagnose and debug this memory growth issue. … Read more
Summary To achieve stable and platform-independent screenshots with Playwright MS Edge, it’s crucial to understand the factors affecting font rendering. Font rendering variations can lead to differences in screenshots between runs on the same machine and between different machines. Root Cause The root cause of the issue is attributed to: Font rendering differences due to … Read more
Summary The issue at hand is a Playwright test timing out after 30 seconds when attempting to create 40 users in a system using a sequential forEach loop. This approach is not scalable and leads to reliability issues. A better approach is needed to handle bulk user creation in Playwright. Root Cause The root cause … Read more
Summary Recursive Common见到了 Table Expressions (CTEs) in SQL Server prohibit aggregate functions (MAX, SUM), TOP, or GROUP BY in the recursive term (the part referencing the CTE). However, a workaround using UNION ALL with an empty set (e.g., WHERE 1=0) unexpectedly bypasses this restriction. This post explores why the restriction exists, why the work parfoisaround … Read more