[mkgmap-dev] RAM and mdr Europa ?

Hi, I have a W10, 64 bit machine and 10 GB RAM. Since a few months i can not generate the mdr-file for Europa from www.Download.Geofabrik.de In a first run i generate only all the maptiles. No Problem. in a second i will generate the overview, tdb and mdr. I start j/ava -Xmx9800m -XX:-UseGCOverheadLimit jar mkgmap.jar code-page=1252 -family-id=1901 -x-split-name-index -index D:\Karten\Europa\*.img./ and get the error. with mkgmap-r3864 it get the same error. How many RAM must i have for Europa complete ?. In august 2016 it was possible to create the mdr with 6 GB RAM. But the filesize is growm ... thomas