After a *lot* of messages like these :

Node 986712679 in too many areas. Already in areas 0xd0a0706, trying to
add area 0xe
Node 986712679 in too many areas. Already in areas 0xd0a0706, trying to
add area 0x11
Node 986712679 in too many areas. Already in areas 0xd0a0706, trying to
add area 0x12

The tracking tables used by the old version of the splitter can only track nodes that occur in at most 4 output files. (To handler borders correctly, nodes near a region are included in it.) The warnings indicate that nodes weren't written to a file that they should have been. That's bad.

I suggest using a copy of the splitter generated from the crosby_integration branch. The code in that branch supports pbf input, runs faster, and doesn't have this limitation. http://www.mail-archive.com/mkgmap-dev@lists.mkgmap.org.uk/msg07266.html

the command

java -jar splitter-r123/splitter.jar --mapid=400 --max-nodes=1000
--resolution=15 iso-nl-259.osm

did produce 30 output files. This may be too much, so I tried again with
max-nodes=10000 (and resolution=15). Similar result : 30 output files.
This time I logged the output via script : > 3 million lines of
messages.

It sounds like the limit is the minimum size of a region. Note that this is a limitation of the part of the splitter that automatically finds splits. If areas.list is manually edited, smaller regions can be generated.

You're hitting that minimum-area-size limit at anything under 10,000 nodes. The only fixes are either increase the resolution, or, for regions containing too many nodes, edit areas.list file and subdivide the regions that are too big.

max-nodes=10000 , resolution=14 --> 6 files, "only" 120000 lines of
output in typescript.

BTW I also tried decreasing max-nodes without changing the resolution,
this is what Felix wrote. That didn't work : the file never got split
further.

So how do I describe what to do, in documentation for RoadMap users ?

First question is how many nodes can RoadMap handle?

Scott