Tag: performance
Event Loop Blocking — Long Tasks
ES5
JavaScript is single-threaded — synchronous code that runs >50ms blocks the event loop, freezing UI and delaying I/O callbacks. Break long tasks into chunks.
2mo ago
javascript intermediate
eBPF — Kernel-Level Observability
Extended Berkeley Packet Filter — a technology for running sandboxed programs in the Linux kernel to trace system calls, network traffic, and performance metrics without modifying applications.
3mo ago
devops advanced
Eager Loading
PHP 5.0+
Loading related data upfront in a single query rather than deferring until access, preventing N+1 query problems.
3mo ago
performance intermediate
Eager vs Lazy Loading — When to Use Each
PHP 5.0+
Eager loading fetches related data upfront in one query; lazy loading defers it until accessed — the wrong default causes N+1 or over-fetching.
3mo ago
performance intermediate
Elasticsearch
PHP 5.0+
1
A distributed full-text search engine — inverted indexes enable sub-second keyword and relevance-ranked search across millions of documents.
3mo ago
search advanced
Event Delegation
ES5 A pattern that attaches a single event listener to a parent element instead of many listeners to children — using event bubbling to handle events from dynamically added children.
3mo ago
javascript intermediate
Excessive File I/O
PHP 5.0+
Reading the same file multiple times inside a loop or across repeated calls — avoidable with simple in-memory caching.
3mo ago
performance intermediate
EXPLAIN & Query Plans
PHP 5.0+
EXPLAIN (ANALYZE) reveals how the database executes a query — sequential scans, index scans, join strategies — to guide optimisation.
3mo ago
database intermediate
EXPLAIN ANALYZE
PHP 5.0+ The database command that shows the actual execution plan of a query — revealing sequential scans, missing indexes, and row estimate errors that cause slow performance.
3mo ago
database advanced