gdal_translate to clip 5x5 degree tiles from a raster.
I have 4 large rasters-- one for South America, and 4 that divide Africa and Asia into 4 separate pieces. Each raster is a Byte, in WGS84, and has values of 1 (land) and NoData (ocean). I can extract a tile from South America like so:
gdal_translate -co COMPRESS=LZW --config GDAL_CACHEMAX 11% -projwin 10.0 -5.0 15.0 -10.0 1.tif my_tile.tif
This takes 40 seconds.
I also have a VRT of all the rasters together, South America and the four other tifs that compose Africa/Asia. To create the same tile, I do:
gdal_translate -co COMPRESS=LZW --config GDAL_CACHEMAX 11% -projwin 10.0 -5.0 15.0 -10.0 gadm0.vrt my_tile.tif
This takes 3 minutes.
Is this expected? Is there any way to cut down on the overhead caused by the VRT dataset? Happy to provide the actual raster data if that helps.
EDIT: See this link for the data associated data: https://www.dropbox.com/s/y20gzv627kyjlwx/SE_Test_VRT_Data.zip?dl=0