Running real services on a small VPS

A lot of what looks like a scaling problem is really a maintenance problem. On a small VPS with a gigabyte or two of RAM you can run a surprising amount — as long as you keep the number of moving parts low and make the boring things automatic.

Keep the request path short

The fastest request is the one you never have to serve dynamically. Static files, cached responses, and a sensible CDN in front of the origin remove most of the load before it ever reaches your box. What is left is usually small enough to fit.

Make the machine easy to reason about

A few rules I keep coming back to:

• one job per container, one process per container;
• explicit resource limits, so one service cannot take the whole box down;
• health checks and restart policy, so failures are boring;
• configuration in files under version control, not in a shell history.

Resources are finite, so treat them as a budget:

# What is actually using memory right now?
docker stats --no-stream --format \
  'table {{.Name}}\t{{.MemUsage}}\t{{.CPUPerc}}'

Back up the small things that matter

Most of a server is disposable. The database, the configuration, and the certificates are not. If you can restore those three, you can rebuild everything else in an afternoon.

Boring, small, and reproducible beats clever, large, and fragile almost every time.

None of this is exotic. It is just a set of habits that keep a small machine honest — and keep you out of the terminal at midnight.