Tagged “performance”

2 posts found.

Jul 9, 2026· 2 min read ·9 views

The N+1 query problem, and why your ORM hides it

One query for the list, then one more per row, forever

Loop bodies that touch the database are the smell.
Log your SQL in development — the count is the tell.
Fix it by fetching related rows in one query, not by caching the symptom.

You fetch 50 posts. Then, for each one, you read its author. That is 1 + 50 = 51 queries where 2 would do. It looks harmless because each individual query is fast. The problem is t…

Jul 8, 2026· 1 min read ·12 views

Why your Docker build takes four minutes every time

Layer caching is ordering-sensitive, and most Dockerfiles get the order wrong

Key takeaways

COPY your lockfile before your source, not with it.
Every instruction after a changed layer is rebuilt.

Docker caches each instruction as a layer. When one changes, that layer and every layer after it is rebuilt. So the order of your Dockerfile decides your build time. The common mis…

docker devops performance