How to serve very large raster datasets

So far in this chapter, we looked at how we can increase the number of raster formats that GeoServer can serve, and considered how we can prepare our raster data for efficient serving. However, in these discussions, we only looked at relatively small numbers of raster images. We have not yet given any consideration to how we might approach the not-so-insignificant issue of serving large volumes of high resolution imagery. For example, how might we approach the challenge of serving raster data at a national scale such as large-scale aerial surveys or a national map product such as Ordnance Survey's OS StreetView?

We can stitch all the individual raster images together to create a single file containing the complete coverage. However, this will result in a considerably large file for processing (and, in fact, one that it might not be possible to store). The OS StreetView product, for example, requires approximately 10,592 files to cover Great Britain...