I have read many strategies for raster performance, but i still have problems with my case. The posts that i have read explain the strategie, but are not very detailed. Im new to mapserver so i have problems implementing them. My case is:
-about 6000 tiles that form the map -170mb each tile -aproximately 1.2T of iamges -i have 10T HD and i think disk space is not a problem for me -tile format is TIF -tile size 9375x6250 pixels The strategy i have implemented and the problems i have -First i divided the tiles in 60 folders, to increase the performance in disk seek/read. -Than i transformed source files into internally tiles with the command gdal_translate -of GTiff -co "TILED=YES" original.tif tiled.tif -i used gdaladdo to add internal pyramids gdaladdo -r average 2 4 8 16 32 64 128 -Created a tileindex using gdaltindex -write_absolute_path MapAll.shp //server/Maps/Subfolder1/*.tif -Created a spatial index .qix file shptree MapAll.shp -than added the layer to the mapfile without the .shp extension so the application can use the .qix as you may know, i have very slow performance when i zoom out and im stucked here. As i have read i should make a copy of the tiles with reduced resolution. Merge the tiles together and use min/max scale to show different layers in different scales. the min/max scales i zoom in/out are 100/1200000. Now my questions are - How can i calculate the scale where i should create another layer of the tiles, or i shoud see it with some tests? - how much should be the resolution of the new layer? - is there any tools or program to merge the tiles? merging 6000 tiles with the gdalwarp by writing the command by myself is frustrating - how many tiles should i merge together to create the new layer? (how many tiles should have the new layer) i know that in each zoomscale its better to appear only one tile but i dont know how to calculate it - the tiles that i should merge are the originals or those with internal tiling and overviews?
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