Don't just reach for something because it has been the most common thing posted on programming forums. The behavioral psychologists and economists consider this a well known cognitive bug.
Yes, zookeeper is a turd, but it's a battle tested turd. Distributed systems aren't easy to get right.
The point being kafka has a very heavy operational overhead and you better understand what you are getting into and what bargain you're making for the scalability you mention.
The fact that you are comparing zeromq to Kafka is pretty good evidence that you have no idea what you are talking about, and are just tossing out names from google. I'm a little disappointed, honestly, I hoped you were aware of something I hadn't heard of.
Sounds like you are unwilling to redefine your problem so that it is amenable to solutions that are not kafka.
I need to durably handle billions of events per day. No amount of redefining changes the underlying business problem.
Kafka, on the other hand, has been helping me solve that problem for years.
But this discussion has devolved into personal insults at this point. We have nothing to teach each other it seems.
It's certainly possible that Rabbit has improved in the years since I used it, if it works for your use cases, great. But don't assume that everyone using a popular technology is doing so because of a fad or without understanding the tradeoffs.
* Re: workload in the 70s. You are missing the point about logistics stacks than handle 1000s of transactions per second. The point is that Uber's problem is self-imposed. Stepping back and thinking about the problem a little will let them handle the same amount of work with 1/10 the hardware costs.
* Re: first version. The first version and the n-th version when properly designed requires the same set of gradual steps. If you build the first version to throw away then whose problem is it that you built it that way and need 10x the hardware to handle the workload because of shitty architecture? Again, stepping back and taking a holistic view and thinking a little bit is the trick.
* Re: extensibility. Same deal. Design your architecture properly and you can extend it as far as any business requirement forces it without spending 10x on hardware and software. How do you do this? Same as above. Thinking.
* Re: reliability. See above. Thousands of transactions a second with unmatched uptime. It is more likely the systems I interface with will go down or even for AWS to have an outage than for a properly designed system to fail.
1. Machine learning - already doing it wrong. You've failed to learn from history and instead are following fads and trends. When properly framed routing/allocation is a linear program and there are solvers than will solve such problems with millions of variables. Instead you have opted to complicate the problems with latest fads and trends that are not even suited to the problem you are solving. In essence you've made my point.
2. Consumer laptop? I'd hope the software runs on server grade hardware. Bringing up a consumer laptop as a restriction on memory is a non-sequitur.
3. Hundreds of thousands. Great. I can handle several thousand connections per second on a dinky c4.2xlarge instance with 10-20ms guarantee with a ruby stack. There are plenty of ways to optimize it further but I've never needed to. The literature is full of optimized and distributed graph search algorithms. Operationalizing any one of them wouldn't be much work. How do I know? Because I've done it before.
4. Reliable data pipelines have been a solved problem since hadoop and friends. This is a solved problem. Again making my point about bloat.
Re: one team over a year. Seems like you need better engineers or better designed systems. If you're developing software with more than 100 engineers and the boundaries between teams are so ill-defined that you need more than 10 per team then that's an organizational problem and highly inefficient way to do things. How do I know? Worked on teams that gelled and those that didn't. The determining factor was always reducing communication overhead by proper architectural design. The amount of communication overhead was almost directly correlated with software bloat and sprawl.
1. Devops: Solved problem. Chef, ansible, puppet. Pick one they're all the same.
2. Kafka is not good software. Pick something else for your event management pipeline. Heck, build it from scratch. Neither Kafka nor Storm are novel or required. Chances are you've over-engineered it if you are reaching for those and need to step back and think.
3. Simplify your call graph. There is no magic bullet here. No amount of dashboards, logs, and metrics will let you get around an ill-designed and bloated service architecture. Again you've made my point.