On Mon, Jul 29, 2013 at 07:47:10PM +0100, Robert Newson wrote: > CouchDB will check that the current revision of every document is > present on the target and will skip copying it if it is. In your case, > the replication will not transfer any documents at all but will check > every id/rev pair which will take some time.
Okay thanks. Is this also true if I pull and push from the same machine. That is, if I set up pull replication on A to pull from B, in parallel with the push from B to A? My understaing is that the two replication jobs (push A to B, pull B to A, both running on A) would be totally independent and would not share information about B's db state. Correct? Thanks, James > > B. > > > On 29 July 2013 19:37, James Marca <[email protected]> wrote: > > Hi, > > > > I have two machines, A and B. I am running an analysis on A, saving > > the output to couchdb, and then replicating by push from A to B. > > > > B's database started life from this push replication, and has never > > been otherwise modified. So the two are more or less identical. > > > > What I want to do now is parallelize my work flow and run more > > analyses on B, save locally (to B's couchdb), and then replicate those > > changes to A. (The database is used both to save output, and also to > > keep track of what has been done already, so it is useful to keep the > > output db syncronized between all machines.) > > > > My question is whether replicating from B to A will require pushing > > all of the docs to A. This is an issue because my database is 21 GB > > and growing, and I'd rather not push all that data from B to A when I > > *know* the two are identical right now. > > > > Is there a way to set up replication to skip everything already there? > > Or to copy the replication state from A to B so that B knows that > > replication with A can start with new data only? > > > > If not, I can of course just save work done on B to the CouchDB on A > > directly, but I'd rather set it up so that the computation process > > always just hits couchdb on localhost, and let couchdb do the machine > > to machine copying. > > > > Thanks for any insights or pointers to the correct docs page, > > > > James Marca
