Hi, I have received temperature map time series of 50 years of daily data in single Geotiff files (Tmin, Tmean, Tmax). Each GeoTIFF has around 21550 bands, 4GB file size.
Problem: the import takes "forever" despite using a superfast disk, i.e. 120 seconds per band (size is only 464 x 201), so 29 DAYS for each file. The problem will be that it has to run through the entire 4GB over and over again for each channel. I guess I want to do heavy caching - but how? Looking at ImportBand() in main.c of r.in.gdal, I see that GDALRasterIO() is used: http://www.gdal.org/gdal_tutorial.html#gdal_tutorial_read but I don't see hints to tell the IO function to keep more in cache. The original files are in netCDF format, I used gdalwarp to generate GeoTIFF. First I thought to write it out as 21550 files but didn't find an option to do so. Clueless, Markus _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
