On Sat, Mar 11, 2017 at 7:01 PM, Markus Metz <[email protected]> wrote: > On Sat, Mar 11, 2017 at 8:53 AM, Nikos Alexandris <[email protected]> > wrote: >> >> Nikos Alexandris >> >>>> Why does (attempting to) import a 38m pixel resolution GHSL [0] GeoTIFF >>>> layer, ie GHS_BUILT_LDS1990_GLOBE_R2016A_3857_38_v1_0_p1.tif, in GRASS' >>>> db progress slow? > > because it is a very large raster map: Size is 507904, 647168
Nikos, for an even bigger map try Global Surface Water (2000-2012, 30 m, Data coverage is from 80° north to 60° south): http://landcover.usgs.gov/glc/WaterDescriptionAndDownloads.php by USGS. 1.6GB in size. Using gdalbuildvrt I created a VRT from the 504 GeoTIFF files. After import into GRASS GIS, here the timings: # final map size: g.region -p ... rows: 493200 cols: 1296001 cells: 639187693200 (handling only works in GRASS GIS 7.3.svn since Markus Metz's recent improvements on global data import are needed). Benchmarks: - Import took 2h while reading the data from a CIFS mounted storage box (slow) and writing on SSD. - Displaying the entire map (639 giga-pixel) in GRASS GIS' display (d.mon) took ~15 sec over a ssh tunnel from my laptop to the server, since I am at a conference. Fair deal I would say :-) cheers, Markus -- https://www.mundialis.de/ _______________________________________________ gdal-dev mailing list [email protected] https://lists.osgeo.org/mailman/listinfo/gdal-dev
