I have a big problem with my vector dataset (more than 1 million entities) and v.generalize in grass 7.0.5 and 6.4 (64 bits for both). I try to use Douglas method on this dataset but it is very very slow and I'm searching how to improve this treatment.
Firstly, i can't split my dataset for this job and I must conserve the topology.
For test, I use the lsat7_2000_80 raster from North Carolina data set for grass 7. Firstly, i vectorise (r.to.vect) this raster in areas with -s flag (smooth corners). I got 1642301 vertices for 224752 areas. Secondly, I use v.generalize with douglas method and treshold 15 meters. This step take 48 minutes (i5 2.6ghz, 8go ram on windows 7 64bits and Ubuntu 16.04 64 bits) and i search how accelerate it.
Does anyone have an idea on how to increase the speed of this tool?