Paul, a post-write filter is to change the response from a call to update, where as a _show is for generating a particular response. I was wondering about being able to add interceptor handlers (filters in the servlet world).
The pmap example was nice, but as you have commented writes are serialized so I will start again! I will look at seeing if I can parallize the json parsing. Norman On Mon, Aug 10, 2009 at 8:00 AM, Paul Davis<[email protected]> wrote: > On Mon, Aug 10, 2009 at 9:53 AM, Norman Barker<[email protected]> wrote: >> I was a little surprised by this, and did a quick grep on spawn on the >> couchdb code base, it isn't used that much and I wonder why. In >> particular for bulk doc updates I wonder why pmap isn't used (perhaps >> I am missing something), for my project I have needed to write a >> custom updater, a pre-writer, (great modular design now btw in 0.9 I >> was able to hook it all up - updater, query server from the ini file) >> and I am going up to a javascript function to parse an incoming >> document (not JSON) into multiple JSON documents I am then using a >> pmap to write this to the db, doesn't seem to be that complicated and >> I should then get an increase in speed to compensate for the initial >> javascript parsing delay. >> >> Could all (or most) use of the plain map be replaced with a pmap in >> couchdb or am I missing something? >> >> Not to hijack this thread, but I have written a pre-writer, are there >> any plans to add filters (pre and post) on the couchdb roadmap? >> >> As a J2EE developer, I still see the benefit of the Erlang VM - easier >> to develop 'fast' applications in for sure. >> >> thanks, >> >> Norman >> > > Couple points, > > All writes to disk are serialized, so using a pmap to save docs isn't > going to save you much unless you're parallelizing the JSON parsing. > > I'm not sure what you mean by pre and post filters. I wrote a first > pass at being able to mutate documents when saving last week or so. > Post filters sounds alot like _show. > > HTH, > Paul Davis >
