Hey James, I haven’t analysed the complexity of the data types. Off hand I know that operations on Maps, Sets, Counters etc are not O(n). Merges sometimes will be, if every entry must be compared, and we’re looking at ways to optimise this. The `value` operation on Maps and Sets must be O(n) since we have to derive the correct value for each entry. I’m not sure how we would optimise that.
We’ve optimised the `context` for operations down to a single version vector (before it was a binary of the entire Map or Set), which should have got us some performance improvements. Right now Sets and Maps still use orddict. We have a round of performance and scalability testing starting, and hopefully some optimisations will come out of that. I think you’re referring to Sean’s porting of Elixir’s TreeMap to erlang. We have not yet tested that code, nor have we integrated it with riak_dt. I don’t know if anyone even plans to. Have you observed poor performance from the data types? The earlier releases' main performance issue was to/from binary encoding. We since switched to erlangs built in t2b/b2t functions, with compression, and have found the performance to be acceptable. I guess the short answer is: we’re working on it, but with 2.0 release looming up, we might not get all the way there in time. There is some cost for using CRDTs, I don’t think it could be another way, there aren’t any free lunches. My aim is to reduce that cost below the pain barrier of siblings, and writing complex merge functions. Cheers Russell On 31 Mar 2014, at 23:06, James Moore <james.mo...@tapjoy.com> wrote: > Hey All, > > has there been any progress on resolving the O(n) behavior of crdt sets and > maps? > > Sean mentioned in a previous thread that there was a potential for a fix to > resolve the poor performance of erlang's orddict. > > thanks! > > --James > _______________________________________________ > riak-users mailing list > riak-users@lists.basho.com > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com _______________________________________________ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
