Hi Gerd,

mkgmap is running now, I'll likely report tomorrow.

But I already saw that the first tile took very long, and in the areas file it is:
43100001: 1765376,-935936 to 2822144,139264
#       : 37.880859,-20.083008 to 60.556641,2.988281

So, I suspect that here could be a problem: some of the newly added extracts inflates the area covered by the map extremely. I first thought of the Dutch Antilles in the Caribean, but that's farther west and farther south. I cannot see how that area comes into the map.

The maps I created before, typically contained Germany, Chechia, Austria, Liechtenstein, and Switzerland. That took normally less than an hour per map.

Now I added Luxemburg, Belgium and Netherlands also, which does not increase file size a lot. But the time for map creation was increased enormously.

Bernhard

Am 21.03.2017 um 09:17 schrieb Gerd Petermann:
Hi Bernhard,

other tests did not show new results. Any idea why you got so different numbers?

Gerd
________________________________________
Von: mkgmap-dev <mkgmap-dev-boun...@lists.mkgmap.org.uk> im Auftrag von Gerd 
Petermann <gpetermann_muenc...@hotmail.com>
Gesendet: Montag, 20. März 2017 07:40:00
An: Development list for mkgmap
Betreff: Re: [mkgmap-dev] Performance with large files

Hi Bernhard,

reg. splitter:
If I got that right you used pbf as input format for the "Germany" result and *.o5m for 
"Central Europe".
Since the o5m format allows faster processing the splitter times are okay for 
me.

reg. mkgmap:
I've added a few lines in mkgmap to report the calculation time for each tile. 
As you might know,
mkgmap starts a few threads (depending on the max-jobs option) and each thread 
processes on tile at a time.
The threads share only a few data structures, and mkgmap doesn't collect much 
information for each tile in
memory, so  there is no good reason for an increase of run time per processed 
tile.

My system is probably close to yours, a machine with 8 GB Memory and a 4 core 
CPU (i5) running a 64 Windows.

The attached patch adds a few lines to report the calculation time for a tile. 
The patched version is here:
http://files.mkgmap.org.uk/download/339/mkgmap.jar

  I've used the patched version to compile a map with the OpenfietsMap Lite 
style of an area around (and including) Germany .
I used the attached dach-x.poly file with osmconvert and a planet.o5m file from 
2017-01-17.
and splitter with max-nodes00000 & keep-complete=true and found what I 
expected.
Times are between 7 and 35 seconds per tile, most are around ~20 secs, no 
increase in time/tile.
The time for the creation of the index / gmapsupp is rather short compared to 
the overall run time.
The complete mkgmap log is here :
http://files.mkgmap.org.uk/download/340/mkgmap_2017-03-20-064126.log

So, I cannot reproduce your result for mkgmap.
Maybe your machine was busy with other work like installing updates, maybe some 
tiles in the added area
require much more time, maybe times depend on program options or style.

I just noticed that I did not enable assertions (-ea) so  I now try a variant 
with a max-nodes00000 and -ea.

Gerd








________________________________________
Von: mkgmap-dev <mkgmap-dev-boun...@lists.mkgmap.org.uk> im Auftrag von Bernhard 
Hiller <b...@gmx.de>
Gesendet: Sonntag, 19. März 2017 19:46:32
An: mkgmap-dev@lists.mkgmap.org.uk
Betreff: Re: [mkgmap-dev] Performance with large files

Eventually I updated Java and tried the latest version of mkgmap 3847
(and also splitter 580).
The extracts were retrieved from Geofabrik on Saturday 18.
Germany: 2.93 GB
plus additional countries: 5.62 GB (incl. Germany) which were combined
to a 7.57 GB o5m file.
splitter: Germany 14 minutes - Central Europe 20 minutes
mkgmap: Germany 30 minutes - Central Europe 133 minutes
While splitter performed better than O(n) (more like O(sqrt(n))),
mkgmap performed worse than O(n^2).

Am 19.03.2017 um 12:06 schrieb Bernhard Hiller:
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.

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