[mkgmap-dev] EU map too big?

I fear that the Europe map became too big for mkgmap to put it into one mapset. I have now 2293 img tiles that I wanted to combine with mkgmap-r3590 The java memory is set to -Xmx8000m, the error message is as follows: SEVERE (MapFailedException): (thrown in BufferedImgFileWriter.ensureSize()) There is not enough room in a single garmin map for all the input data. The .osm file should be split into smaller pieces first. There is not enough room in a single garmin map for all the input data. The .osm file should be split into smaller pieces first. What does this mean? Is my index file too big? Is there another way to combine the img tiles to make a single mapset?