Hi Bernhard, if you see a different picture with the current version, please let me know. One effect that might cause longer run time for later processed tiles is the String.intern() method or Gargabe Collection in general.
Gerd ________________________________________ Von: mkgmap-dev <[email protected]> im Auftrag von Gerd Petermann <[email protected]> Gesendet: Sonntag, 19. März 2017 12:16:54 An: Development list for mkgmap Betreff: Re: [mkgmap-dev] Performance with large files Hi Bernhard, the calculation time per tile can depend on map elements, e.g. complex multpolygons may result in additional seconds. Besides that there should be a O(n) calculation time. The final step however is typically to calculate the index , and that step reads data from all tiles, so it depends on the amount of data. Note the hint about --index in the help: If both the --gmapsupp and --tdbfile options are given alongside the --index option, then both indexes will be created. Note that this will require roughly twice as much memory. Gerd ________________________________________ Von: mkgmap-dev <[email protected]> im Auftrag von Bernhard Hiller <[email protected]> Gesendet: Sonntag, 19. März 2017 12:06:31 An: [email protected] Betreff: [mkgmap-dev] Performance with large files How is mkgmap expected to behave when input files grow in size? Is a linear inrease in calculation time - i.e. O(n) - expected, or an increase beyond linearity? E.g. when I create a map with routable lines for bicycle, mkgmap takes some 30 minutes for Germany alone (3 GB pbf file resulting in 850 MB img file), but more than 2 hours for Germany and some neighboring countries (7 GB o5m file, resulting 1.4 GB img). Are there many calculations at O(n^2) or beyond in mkgmap, or is this due to other factors, e.g. memory limitation? Notes: mkgmap is called by %JAVA% -Xmx6800M -ea -jar %MKGMAP% .... on 64bit Win 7; swapping to disc does not occur. But I am more interested in a general rule than in some hints for improving the performance in this concrete case. E.g. how I could estimate the duration if I add some further countries... Thanks for your hints. _______________________________________________ mkgmap-dev mailing list [email protected] http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev _______________________________________________ mkgmap-dev mailing list [email protected] http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev _______________________________________________ mkgmap-dev mailing list [email protected] http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
