[gdal-dev] GDAL slow to write GeoTIFF?

[Graeme B. Bell]

Gdal doesn't do well with ultra-large rasters in my experience.

Locally we split our rasters up into tiles, process tiles in parallel with Gnu Parallel, then use gdal_merge or gdalwarp to join them back together (usually gdal_merge is faster).
This usually brings our processing times on high res national rasters down to tens-of-minutes instead of days. 

If the raster is formed from original polygon data e.g. gdal_rasterize output, be sure to use compression, it will improve performance and file storage by 1-2 orders of magnitude. 

Graeme.