[solved] How to maximize CPU cores usage when building the graph?

[culebron]

My question might be repeated, but I can’t find anything with googling.

So, on my laptop Graphhopper uses 2-8 cores out of 8. But RAM is not enough.
On a server with 128GB RAM and 48 cores, it uses only 2…10 cores, most time 2-4.

Is there a setting limiting this that I can change?
Simple question, but can’t find anything.
Thanks!

P.S. For comparison, OSRM uses all available cores, and on this 48-core machine, entire Russia graph is built within minutes, while on a 4-core machine it takes >1 hour.

[karussell]

The import process is only parallelized regarding the file reader (2 threads) and regarding the vehicle profiles. There is no possibility to use more CPUs and make the import faster. But often the disk speed and RAM speed (and size) have more impact on the import time.

But RAM is not enough.

What do you mean here?

[culebron]

Ok, thanks!

@karussell

What do you mean here?

I’m trying to build a strange GTFS feed that won’t build even on Xmx32g. I started a separate thread on it: [solved] Saint Petersburg GTFS (smaller than Berlin's) needs 40 GB of heap memory. Why? - #2