[dlsspy]

memcached (binary) protocol for both doc manipulation and "changes" helps performance considerably. We looked at inventing a new protocol to stream stuff in and out faster, but we decided to go with the one we already had. Though the internal APIs have been shifting a bit, it was built entirely without touching the couchdb core and gave us a huge performance benefit over http: https://github.com/couchbase/mccouch

rewriting (not core, but slow) components in C is always the right way to do this sort of thing. We've been in the process of building a NIF for document updates for a while now (TBH, I don't know where the source is off the top of my head, but we don't keep stuff closed). We've got massive performance gains in pure erlang, but we expect to cut CPU consumption down more with this new code. It's intended to be available to Apache CouchDB if they want it.

I like CouchDB a lot myself, and use it for lots of projects (including critical parts of couchbase, inc.). If we can't solve the same problems with the new product, we'll know it because we use it ourselves.