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Comment by masleeds | Hacker News Reader

Riak has been maintained through the post-basho years by engineers at some of its larger customers (disclaimer - including myself).

The focus has been on trying to improve the stability of the database when subject to complex failure scenarios under stressful load, with minimal need for urgent operator intervention. The focus has been on keeping those existing operators happy rather than seeking out new users. Evolution of the product since basho has been slow but significant.

The project now has support from Erlang Ecosystem Foundation, and we're looking to invest some effort over the next few months explaining what we've done, and to start to articulate what we see as the future for Riak. So if you're interested watch this space.

It is expected to remain a niche product though. However, it may still find a home for those demanding specific non-functional requirements, with an acceptance of some functional constraints.

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Metastability is an under-rated system property for databases and systems software, in general.

What does metastability mean in this context? I've only seen it used to mean "appears stable but not actually stable", eg systems that resist small perturbations but never return to nominal after bigger disturbance (like cold boot).

Did you mean "stability"?

Marc Brooker’s blog on the topic is good: https://brooker.co.za/blog/2021/05/24/metastable.html

That's exactly what I mean, that's why I'm asking what GP meant.

I'm not aware of any definition of metastability that would be a desirable property of a system. Vaguely speaking, in my understanding metastability in physics, chemistry and electronics refers to a state that has not yet fully settled and the final state is therefore undeterminable / random.

Could you elaborate your understanding of the term? I can see it related to concepts like eventual consistency, just unclear of how it would be considered a positive characteristic. I'd have thought that a deterministic outcome would be important in a database system?

Did you mean 'not remaining in metastable failure' ?

I was under the impression that once you learned how to pet the cat forwards (the non-triviality of getting to that point being an oft cited adoption barrier, but still), Riak was really quite excellent at recovering from things going wrong, which would fit with that being what you were trying to say.

Or maybe my guess has gone completely wide, in which case please do break out the small words and crayon drawings and explain what you actually meant :)

> we're looking to invest some effort over the next few months explaining what we've done, and to start to articulate what we see as the future for Riak. So if you're interested watch this space.

Where's that going to be posted? I'm not a Riak user but I am interested in hearing what others are doing in regards to improving failure scenarios in distributed systems.

When we get stuff together there will be a link from our discussions page - https://github.com/orgs/OpenRiak/discussions.

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