5 ms·
How about having the state 100% on server AND on client? No dragons, no problems.
by hem777 4y ago
How about having the state 100% on server AND on client? No dragons, no problems.
- treis 4y agoKeeping them in sync is the dragon
- mlajtos 4y agoCRDT is the dragon slayer
- iamwil 4y agoIt's the sword that we needed! But it doesn't take us all the way. There are semantic conflicts that are difficult for CRDTs to solve alone.
- hem777 4y agoWhat are the semantic conflicts you mean here? As far as I can tell, CRDTs are the correct solution for syncing state between parties.
- towawy 4y agoMerge conflicts that must be resolved by the user (i.e. when there is no logical way to determine the priority of two offline changes) are still an application specific problem, even with CRDTs. You can build structures that allow storing conflict resolutions in CRDTs, but getting them right is still like half the problem to solve.
- mlajtos 4y agoYes, sometimes it is hard to come up with the merge strategy that preserves user intent. I think the big one is rich text, where Peritext[0] looks like a good direction. [0]: https://www.inkandswitch.com/peritext/ https://www.inkandswitch.com/peritext/
- hem777 4y agoI have lack of imagination to think what kind of conflicts those would be, would you have examples? In my experience there’s always a logical way to solve conflicts. And CRDTs can have any kind of conflict resolution algorithm, so it’s customizable per application. “Storing conflict resolutions”, eg. “a merge operation”, is not needed and unnecessarily complicates any CRDT.
- hem777 4y agoThis is the correct answer :)
- rs999gti 4y agoHow do you prevent sync issues? One local DB/store for each app. Who is the correct sync? Or is it first in first out?
- hem777 4y agoCRDTs is how sync issues become non-issues. The “correct sync” is deterministically determined by the CRDT conflict resolution algorithm. There can be multiple DBs/stores per app or per user or per whatever makes sense. One big global DB/store broken down to millions of DBs/stores.
- ohgodplsno 4y agoThen you get to deal with conflict resolution, which is a rare dragon that is kind of confusing and sometimes has to ask the user which state they'd like to keep.