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<div class="moz-cite-prefix">Hi Ludwig,<br>
<br>
> Is the impact of these settings bigger for larger areas
(longer routes)
<br>
> and less important for areas like individual cities with
shorter routes?<br>
<br>
Exaclty. Test if you have enough memory for the longest possible
route. Also there is a problem on master if there are disconnected
areas - see issue 105. Or throw away unlikely points in your
algorithm (queue + map) if memory is too low, at a later stage
graphhopper can do this automatically, but not yet implemented.<br>
<br>
To further increase speed on Android<br>
* you can try AStarBidirection and tune the approximation - the
lower the faster but the probability increases to create
non-optimal routes. Reducing this should also lower the memory
requirements.<br>
* for small areas you can try in-memory instead of mmap graph
(e.g. via hopper.setInMemory(true, true)). But of course this
would require you even more RAM. <br>
<br>
The good thing about none-CH is that you can offer your users a
customizable profile which they are able to tune differently for
every query. For CH you need to know those details upfront.<br>
<br>
Regards,<br>
Peter.<br>
<br>
</div>
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cite="mid:CAAvpVPDXB3DiyrNERaJ3uG-gZKzeghuV96FOpnLEEjzze28P=w@mail.gmail.com"
type="cite">
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<div>
<div>To prepare routing files for more than one vehicle
type at once, I have to comment out<br>
<br>
#prepare.chShortcuts=fastest <br>
<br>
and then also in the Java code add<br>
<br>
setCHShortcuts(false, false);<br>
<br>
</div>
This setting for the generator creates significantly
smaller routing files, which is a good thing, but it
disables the use of the contraction hierarchies, which
should slow run-time route generation down. <br>
<br>
</div>
I have not actually measured the slow-down, but on the
Android devices that I tested it still feels pretty fast,
certainly fast enough, particularly when considering that
the files get much smaller. <br>
<br>
</div>
Are there any worst case scenarios that I should be aware of?
Are there any other trade-offs (such as larger memory use,
inability to find certain routes)? Is the impact of these
settings bigger for larger areas (longer routes) and less
important for areas like individual cities with shorter
routes?<br>
<br>
</div>
Ludwig<br>
</div>
<br>
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