Index: trunk/native/linux/latest/etc/default/josm-latest
===================================================================
--- trunk/native/linux/latest/etc/default/josm-latest	(revision 19018)
+++ trunk/native/linux/latest/etc/default/josm-latest	(revision 19215)
@@ -3,5 +3,5 @@
 
 # Increase usable memory
-#JAVA_OPTS="-Xmx2048m ${JAVA_OPTS}"
+#JAVA_OPTS="-XX:MaxRAMPercentage=75.0 -Xms256m ${JAVA_OPTS}"
 
 # Enable OpenGL pipeline (2D graphic accelerators)
Index: trunk/native/linux/latest/usr/bin/josm-latest
===================================================================
--- trunk/native/linux/latest/usr/bin/josm-latest	(revision 19018)
+++ trunk/native/linux/latest/usr/bin/josm-latest	(revision 19215)
@@ -58,4 +58,10 @@
 fi
 
+# If there is more than 8G ram, we can use up to 75% of the memory while still leaving 2G for other things.
+if [ "$(free --mega | grep '^Mem:' | awk '{print $2}')" -gt 8192 ]; then
+    # But don't set anything if JAVA_OPTS is already set.
+    JAVA_OPTS="${JAVA_OPTS:=-XX:MaxRAMPercentage=75.0 -Xms256m}"
+fi
+
 JAVA_OPTS="-Djosm.restart=true -Djosm.dir.name=JOSM-latest -Djava.net.useSystemProxies=true $JAVA_OPTS"