[OSM-talk] osm2pgsql

[Jon Burgess]

On Fri, 2009-06-26 at 23:44 +0100, Jon Burgess wrote:
> On Fri, 2009-06-26 at 18:28 -0400, James McManus wrote:
> > 
> > But it runs for hours and uses up all of my RAM.  I eventually have
> to kill it. 
> > How long should it take to subset a small area such as this?
> 
> How much RAM and swap do you have?
> 
> It take at least 2 hours to process the full planet, this is time
> taken
> just to do the bzip2 decompression and XML parsing without even
> writing
> anything out to the database. There is a lot of data in the full
> planet
> file.
> 
> The algorithms in the code are optimised for the full planet import
> and
> are not as efficient as they could be for very small areas.
> 
> Using the --slim option should fix the memory issue.
> 
> Alternatively you could start with a UK or England only extract and
> save
> yourself a lot of bandwidth and import time.

To give you some firm numbers, the full planet import on the main tile
server with 12GB of RAM takes around 12 hours. On my home machine I
normally import a UK only planet file and it takes about 15 minutes and
about 2GB of RAM.

The --slim option reduces the RAM usage but the import time will
increase if you have less RAM to cache the DB in memory during the
import.

	Jon