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Comment by WeaselNo7 | Hacker News Reader

Strange to see a lock-free ring buffer without seeing mention of LMAX/Martin Thompson's Java Disruptor (https://github.com/LMAX-Exchange/disruptor)

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I don't think I even saw this until I published the article. I don't think it was academically published, or googled well back in 2000. Nor did it match my needs for a ring buffer at the time, which was to drop stale data (I think in that algorithm, write operations fail when the buffer is full), so if I did see it, I wouldn't have payed enough attention to notice if it even had users. It's good work for sure, but that's why it didn't get mentioned.

Eh, I get it. I also independently came up with these MPMC approaches before hearing about LMAX. They're not entirely trivial but they do follow fairly naturally from the problem space when you really think about it. It's a good piece of engineering, but the one thing that's really unique about LMAX is the amount of advertising it gets.

> the one thing that's really unique about LMAX is the amount of advertising it gets.

Virtually zero? I have to go out of my way to remind HN it exists while everyone is 300+ comments deep into reinventing the wheel on a ~quarterly basis.

Right buffer is a relative obvious and simple idea. For some reason the Java-OOP crowd keeps thinking that LMAX deserves a nobel price for being neither first nor last to use it.

> have to go out of my way

Yeah, that's exactly the annoying part. Can't mention ring buffer ever without someone bring up LMAX. "But do you know, that some Java developers somewhere once wrote something that didn't completely ruin the hardware performance?! It's stunning and amazing."

IMO the take-away from LMAX is not ring buffers - it's the knowledge of how much useful work a single CPU core can do. It's a story of playing to hardware's strengths instead of wrapping yourself up in bullshit excuses. They realized their problem was fundamentally not parallelizable, so they wrote it to run serially as fast as possible instead of wrapping themselves up in bullshit excuses, and the resulting performance was much faster than anyone would have ever guessed if they hadn't done it.

I am not sure why this is annoying. Some problems can be solved comprehensively. This is a pretty good example of one. It might be better for us to focus our attention on other aspects of the problem space (the customer/business).

There are a lot of algorithms that get passed around in java because they can deal only with pointers and pretend memory allocation and deallocation doesn't exist and doesn't lock. I'm not convinced it actually makes sense to use java as a reference language for lock free algorithms because it expose all the details.

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