Hi, would it be okay to change the BoundaryPreparer so that it (optionally) stores data in a Derby DB instead of keeping everything on the heap? http:////http://www.oracle.com/technetwork/java/javadb/overview/index.html Java DB Due to the growth of the OSM data I can no longer create europe *.bnd files with -Xmx2800m (which seems to be the max. value on my machine) I think the current process of extracting boundary data with osmconvert and osmfilter is already quite complex, and maybe a simple DB will help. The idea: The BoundaryElementSaver could store the data in a DB(maybe only the coord data). This would allow to create the *.bnd files with less than 1GB of memory. Any objections against this? Gerd -- View this message in context: http://gis.19327.n5.nabble.com/creating-precompiled-boundaries-with-Derby-DB... Sent from the Mkgmap Development mailing list archive at Nabble.com.