Que VS starqueue

> Can you define "low throughput"?

<1000 messages per minute

Not saying SKIP LOCKED can't work with that many. But you'll probably want to do something better.

FWIW, Que uses advisory locks [1]

[1] https://github.com/que-rb/que

Probably worth mentioning that aside from delayed_job there are at least two more modern alternatives backed by the DB: Que and good_job.

Good article. Sidekiq is a good, well respected too. However if you are starting out I would recommend not using it, and instead choosing a DB based queue system. We have great success with que, but there are others like good_job.

(not sure why this comment was dead, I vouched for it)

There are a lot of ways to implement a queue in an RDBMS and a lot of those ways are naive to locking behavior. That said, with PostgreSQL specifically, there are some techniques that result in an efficient queue without locking problems. The article doesn't really talk about their implementation so we can't know what they did, but one open source example is Que[1]. Que uses a combination of advisory locking rather than row-level locks and notification channels to great effect, as you can read in the README.

[1]: https://github.com/que-rb/que

https://github.com/que-rb/que

This one seems to be the most performant. By a lot too, from my understanding (haven't ran any benchmark myself, but the readme shows some good postgres knowledge)

Que seems like a good alternative if one doesn't want to use Reids. However, given that most apps need Redis (and have it within their infrastructure) nowadays, I still think that Sidekiq is the better option in the generic case.

Implementations that use advisory locks like https://github.com/que-rb/que are much more efficient (atleast when I last tested) and will easily reach 10k job/s on even very modest hardware.

There is a Go port of Que but you can also easily port it to any language you like. I have a currently non-OSS implementation in Rust that I might OSS someday when I have time to clean it up.

It’s also possible to use advisory locks to implement a job queue in Postgres. See e.g. Que[1]. Note there are a fair number of corner cases, so studying Que is wise if trying to implement something like this, as well as some (a bit older) elaboration[2].

We implemented a similar design to Que for a specific use case in our application that has a known low volume of jobs and for a variety of reasons benefits from this design over other solutions.

[1]: https://github.com/que-rb/que

Do also take into consideration que-scheduler (disclaimer, am author). It is built on top of the robust que async job system.

MS SQL server, Postgres and MySQL all support SKIP LOCKED, which means they are all suitable for running queues.

I built a complete implementation in Python designed to work the same as SQS but be more simple:

https://github.com/starqueue/starqueue

Alternatively if you just want to quickly hack something into your application, here is a complete solution in Python with retries:

    import psycopg2

I wrote a message queue in Python called StarQueue.

It’s meant to be a simpler reimagining of Amazon SQS.

It has an HTTP API and behaves mostly like SQS.

I wrote it to support Postgres, Microsoft’s SQL server and so MySQL because they all support SKIP LOCKED.

At some point I turned it into a hosted service and only maintained the Postgres implementation though the MySQL and SQL server code is still in there.

It’s not an active project but the code is at https://github.com/starqueue/starqueue/

Hi folks,

This is a project I wrote and since I am doing nothing with it any more I thought I would publish the source code in case anyone finds it interesting.

https://github.com/starqueue/starqueue/

StarQueue is a message queue server written in Python.

It is designed to be a more simple copy of Amazon Simple Queue Server.

Clients access it via HTTP. The API is documented at https://github.com/starqueue/starqueue/tree/main/starqueueserver/website

The database is Postgres.

When I developed it initially, I included seamless support for Postgres, MySQL and Microsoft SQL server.

At some point in the development I gave up on all databases except Postgres, though I have left the MySQL and SQL server code in place.

I deployed StarQueue as an online service at one point (no longer online). This github repo is a copy of the source code for that service.

This project is not live and is archived, but I have posted it here in case anyone finds the source code interesting.