> There's usually (almost always) durable storage required somewhere.
Despite the name, mnesia can provide durable storage, without using anything outside of OTP and your nodes' (hopefully durable) filesystems.
Despite the name, mnesia can provide durable storage, without using anything outside of OTP and your nodes' (hopefully durable) filesystems.
The main benefit was the ability to load and store Erlang terms natively, along with the fact that it's just a library. The fact that your compute is colocated with your storage lends itself to a different architecture than when you use, say, a stateless web service in front of a relational database.
(Edit: I realize now that I'm replying to a WA old-timer so I'd be curious to know what your assessment of mnesia is with the benefit of hindsight.)
I'm not too worried about a lack of experts and documentation. If you operate at the limits, you'll just need to become an expert, and the source code will be your documentation; mnesia is all written in Erlang, and not too hard to follow; most people won't hit the limits of ets, I'd think. If you don't operate at the limits, you might not need an expert, and if you keep up with OTP releases and hardware releases, the limits get bigger every year.
Looking back, I think we should have spent more time earlier on using the hooks mnesia provides to make healing clusters take less effort; and maybe some automation on cluster expansion. Of course, WA never shied away from manual work by server engineers. :)
(Hmmm, now I'm trying to figure out you are, send me an email if you will :)
Which is why I'm happy others have paved the way.
A huge amount of web apps can get by with a Postgres backed queue that won't break a sweat handling a few hundred writes per second on a low end cloud hosted VPS.
While leveraging something like Oban you don't even need to be an expert. You can just use the library, throw work into it with a reasonable amount of foresight / best practices and you can start developing features in your app.
Anyway, I do not think Mnesia is a particularly good way to persist stuff, just use postgres.