Hi WanMil, I tested the patch with my tiles for Saarland. I can confirm a reduction of processing time ~ 6% compared to r2160, and also a reduction for the peek value of heap memory usage (238M -> 210M), so that's both good! BUT I also see a difference in one of the seven output img files (plus the resulting gmapsupp.img), and I think this is not intended. Both files have the same size, but are different in many bytes. Let me know when I should send details, maybe the new result is better than the old ;-) Ciao, Gerd WanMil wrote
The 2nd patch fixes the remaining problems: 1. Ways without tags but referenced by relations are no longer removed (they might be tagged by the relation style file and could therefore appear in the map) 2. Intersection of ways with the tile bounding box is now checked instead of only checking that at least one point is contained in the bounding box. Only very few ways are affected by this but otherwise routing problems are possible.
The performance improvement seems to be good (measured with my test map): r2159: ~250s patched: ~225s
I also expect (although I haven't tested) that the max memory requirement of mkgmap is decreased. I think max mem is used when the style file is just processed. At this stage all raw OSM elements and all style file processed elements are kept in memory. With the patch the number of OSM elements is noticeably reduced.
WanMil
Hi,
this is another performance improvement:
Usually the mkgmap input tiles are larger than the processed bounding box (splitter parameter overlap). So there are much many elements which are processed but thrown away at a late step in mkgmap.
The patch tries to remove them much earlier before the style files are processed and before the LocationHook starts (which ignores them but that must also be calculated).
The patch contains one drawback: Ways which have all its points outside the bounding box of the tile but which cross the tile are also removed. If that's a point the patch must be improved.
Have fun! WanMil
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