[OSM-dev] OSM and CouchDB/GeoCouch

[Serge Wroclawski]

On Sun, Jul 4, 2010 at 7:51 PM, Lars Francke <lars.francke at gmail.com> wrote:
>> It looks like our schemas are mostly identical, but in my experience,
>> MongoDB used more and more time importing the index as the import continued.
>> An import of the dataset for TX took several hours, but import speeds
>> dropped off markably as the import continued and, presumably, as the
>> geoindex grew.

You should be aware the newer versions will use a slightly revised
schema that doesn't have history (XAPI doesn't need it and we have
other ideas for history).

> This is just a hunch so I might be wrong. Worth checking out though:
>
> Normally you shouldn't use indexes when doing a large import. Just
> create them after the import has finished. This is due to the constant
> need to rebalance the Tree (which I presume they use for the index).

This is 100% correct, and newer versions of the code do this, which
adds a huge speed boost.

- Serge