knktc's Notes

Query RabbitMQ queue length through Celery and Kombu, and purge a queue when needed.

Avoid creating new migrations every time a choices list changes by generating model choices from a helper function.

If pgpool2 closes idle client connections before Django notices, manually closing Django DB connections can avoid OperationalError in long-running tasks.

Use broker_transport_options to limit producer retry behavior so apply_async and delay do not hang indefinitely when the broker is unavailable.

A personal step-by-step note on lowering pressure on a Bosch wall-mounted gas water heater after the pressure gauge climbed too high.

If a remote Python 3 script fails with UnicodeDecodeError over SSH, mismatched locale environment variables between client and server may be the cause.

Build a lightweight asynchronous task queue with uWSGI's built-in spooler instead of introducing Celery, RabbitMQ, or Redis.

When Docker cannot start because its graph directory is corrupted, cleaning /var/lib/docker may be the only practical recovery path.

A practical way to duplicate a KVM snapshot by copying the qcow2 image and adapting the exported libvirt snapshot XML.

On systems where Python 2 and Python 3 coexist, uWSGI may start with the wrong interpreter and fail to import Django.