Hello list, thanks for the comments reqarding patchv5. Attached is one more patch to be applied against the branch. Changes: - Enhanced dictionary size to 65535 - Avoid allocating chunks (short[] objects) with a size that is not a multiple of 8 (r189 wasted 4 bytes for each chunk) - introduced special code for one-value-chunks - max-areas=255 is the default again, but maximum allowed is now 2048 I did not find a simple way to allow also "auto" for the parameter optimize-mem. Maybe Steve or WanMil can help? auto should set optimize-mem=true if Runtime.getRuntime().maxMemory() < 2GB Remarks regarding performance: On WinXP systems, use java -Xms1600m -Xmx1600m -jar splitter.jar ... On 64bit boxes use also -XX+UseCompressedOops This avoids a lot of GC work. I did not yet try that with very large files like europe.osm.pbf. http://gis.638310.n2.nabble.com/file/n7008720/memory_patch_v6.patch memory_patch_v6.patch Some numbers for splitting germany.osm.pbf: patchv6 with -Xms and optimize-mem=true: 588s patchv6 with -Xms and optimize-mem=false: 594s patchv6 without -Xms and optimize-mem=true: 651s patchv6 without -Xms and optimize-mem=false: 622s r189 without -Xms and optimize-mem=false: 639s -- View this message in context: http://gis.638310.n2.nabble.com/PATCH-v6-splitter-memory-usage-tp7008720p700... Sent from the Mkgmap Development mailing list archive at Nabble.com.