On Mar 24, 2011, at 9:01 PM, Damien Katz wrote: > After discovering the huge amounts of CPU we spend parsing and encoding > JSON, I've been working on getting big num support into Paul Davis's JSON > NIF parser so we can include it in CouchDB a get nice performance win. I'm > really loving the NIF interface and it's potential to give us performance > boosts in CouchDB's CPU intensive areas. With the NIF support, we are > going to see a much faster CouchDB. > > However, the problem is they don't work pre R14B. > > So to include NIF functions and get the gains, either we need to raise the > minimal Erlang version of trunk CouchDB for R14B, OR have both a slow > erlang version of the NIF for older version, and fast NIF version for > newer versions and a way to load the different versions. Maybe the NIF > system has that stuff built in, or maybe we can do it somehow with the > build system. > > Since this is trunk, we'll be raising the minimal version of something > like 1.2, not 1.0.3, for example. Anyway, wanted to get that out there and > see what people think about how to handle it. > > -Damien
I have no qualms about raising the minimum required Erlang version, but I thought NIFs naturally allowed for pure-Erlang alternative implementations. From http://www.erlang.org/doc/tutorial/nif.html: > [A]ll NIFs of a module must have an Erlang implementation as well. Normally > these are minimal stub implementations that throw an exception. But it can > also be used as fallback implementations for functions that do not have > native implemenations on some architectures. Regards, Adam
