Debugging
2 articles
A docker pull That Never Finished, and the Swap Behind It
A docker pull stuck indefinitely on 'Pulling fs layer' with no error, no timeout, and one cryptic containerd log line. Here is the full elimination chain that found the real cause, going from DNS to registry reachability to an MTU theory and finally to memory. The answer was swap exhaustion during layer extraction, not a transfer problem.
The Doctrine Filter That Only Breaks on Sub-Requests
A tenant-scoping filter that works perfectly under load, in every test, on every page, until one template embeds another controller.