This benchmark is probably as far removed from how applications use task queues as it could possibly be. The headline is "1 million jobs per minute", which is true. However...

- this is achieved by queuing batches of 5000 jobs, so on the queue side this is actually not 1 million TPS, but rather 200 TPS. I've never seen any significant batching of background job creation.

- the dispatch is also batched to a few hundred TPS (5ms ... 2ms).

- acknowledgements are also batched.

So instead of the ~50-100k TPS that you would expect to get to 17k jobs/sec, this is probably performing just a few hundred transactions per second on the SQL side. Correspondingly, if you don't batch everything (job submission, acking; dispatch is reasonable), throughput likely drops to that level, which is much more in line with expectations.

Semantically this benchmark is much closer to queuing and running 200 invocations of a "for i in range(5000)" loop in under a minute, which most would expect virtually any DB to handle (even SQLite).