Hi Felix, I am not sure but I think a JRE 8 will not execute a jar file compiled with JDK 9 or higher. So, I was only talking about using a newer JRE. I don't know when we will start to compile with 9 or higher. If I got that right JDK 9 is no longer available, so we probably have to switch to 10 or higher. Gerd ________________________________________ Von: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> im Auftrag von Felix Hartmann <extremecarver@gmail.com> Gesendet: Mittwoch, 16. Mai 2018 16:05:50 An: Development list for mkgmap Betreff: Re: [mkgmap-dev] Performance hints for Java JRE 9 + 10 Hi Gerd, What about if you compile mkgmap with java 9 or higher - and run it on Java 8 - this also applies or not? Or asked differently - is this dependant on the compilation system or on the executing system? Felix On 16 May 2018 at 15:53, Gerd Petermann <GPetermann_muenchen@hotmail.com<mailto:GPetermann_muenchen@hotmail.com>> wrote: Hi all, it seems that the new Garbage Collector (G1GC) that was introduced with Java JRE 9 causes longer run times for splitter and mkgmap. I've played with some options and found that the use of -XX:+AggressiveHeap seems to be a good idea when you use these newer JREs. Without this option the java programs tend to allocate more memory and thus the OS might start to swap. Gerd _______________________________________________ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk<mailto:mkgmap-dev@lists.mkgmap.org.uk> http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev -- Felix Hartman - Openmtbmap.org & VeloMap.org Schusterbergweg 32/8 6020 Innsbruck Austria - Österreich