the osm2city software should be changed to use an osm2pgsql database
instead of an osmosis database. Not only can a planet be imported in
less than a day with osm2pgsql (if you have SSDs), but also the
osm2pgsql database already has correctly built geometries for all
objects, whereas osm2city has to make an effort to build these
geometries from raw OSM data,thereby re-inventing the wheel when it
comes to the interpretation of multipolygon relations, the treatment of
way-based vs. relation-based polygons, etc.

osm2city does not seem to use anything that could *not* be found in an
osm2pgsql import.

If you insist on continuing down your current path then you must either
equip your computer with fast SSDs, or temporarily rent a large-SSD
Amazon instance on which you can do your import and then copy over the
resulting database (if you choose a setup where the importing instance
has the same CPU architecture, as well as exactly the same OS and
PostgreSQL/PostGIS versions, then you can copy over the raw database
directory). But even this is likely to take at least a week if not
several for the import - osmosis imports are just not something people
do normally on a planet scale.

I have only cursorily looked at the osm2city source code and it seems
that it uses most of OSM's data (buildings, roads, landuse). If you
should be in a situation where you only need some of OSM's data then a
speedup could be gained by first running "osmium tags-filter" to extract
the data you really need from the planet file. But if the list of "data
you need" contains roads and buildings and landuse then you might as
well not filter, since those categories make up the bulk of OSM data.


Frederik Ramm  ##  eMail frede...@remote.org  ##  N49°00'09" E008°23'33"

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