The posts in Kbin don’t seem to move much the last few days I’ve been using it, but if I go somewhere like lemmy.world the content is always pretty fresh
Is KBin just slow or is there something fundamental I don’t understand about federation? (Likely)
Yes it seems kbin is quite slow at times with fetching posts. I often have to check magazines I subscribed to to see if I did not miss something.
Yes, it seems like information doesn’t get updated fast enough. I went to my subscriptions page and it says the last time someone posted to askKbin was 5 weeks ago. I go to the magazine, there’s a post that’s only 21 minutes old. Kbin isn’t the only place with kinks to work out, though. Pretty much all of them are slow on the uptake, so to speak.
Every instance has two queues - and outbox and an inbox. Either or both of those, on lemmy.world or kbin.social or both, could be full, leading to federation delays.
If you see a post on lemmy.world that doesn’t exist on kbin then it could mean the post is still in the Lemmy outbox OR in the kbin inbox. Both servers are popular so it could be either.
It would be helpful if queue sizes were shown on a status page somewhere…
Lemmy uses a rust back end which basically compiles to native code. By contrast, kbin uses a php back-end.
In my experience, that has a big effect on the speed of federation. My first brush with the fediverse was friendica which is php. It had a lot of really great features, but the one thing that I just couldn’t deal with was the slow speed of federation. My instances aren’t like lemmy.world or kbin.social, pretty much every message comes from somewhere else. The better federation works, the better my experience.
How much data is pushed through ActivityPub? Unless it is at least tens of thousands of requests/events (i’m not familiar with how it works) per second I doubt that the choice of language would have big impact. PHP is made specifically for web backends after all.
As far as I understood it, all updates first get into a queue and are sequentially processed, to keep the strain on the server as low as possible.
I have noticed my instance dmv.pub eventually seems to stop federating (or stop pulling in federated content) at some point, and won’t start again until I restart it. Then it immediately pulls everything in. I need to track down the time when it stops federating and check the logs.