Personal website and blog of Simon Hørup Eskildsen about napkin math, computers, books, ideas, and whatever else interests me.
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Docker’s momentum has been increasing by the week, and from that it’s clearly touching on real problems. However, for many production users today, the pros do not outweigh the cons. Docker has done fantastically well at making containers appeal to developers for development, testing and CI environments—however, it has…
Recently the team I work with completed a project to allow Shopify to run in multiple datacenters . This project was a refactoring project in disguise. When you undertake large refactoring of a code-base with 100s of developers and 100,000s of lines of code, you can’t align by sending an email. The merge-conflicts a…
In this edition of Napkin Math, we’ll invoke the spirit of the Napkin Math series to establish a mental model for how a neural network works by building one from scratch. In a future issue we will do napkin math on performance, as establishing the first-principle understanding is plenty of ground to cover for today!
Composite indexes aka multi-column indexes are about 10x faster than index merges. In Postgres, the gap is larger than in MySQL because Postgres doesn’t support index-only scans for queries that involve index merges.