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Recap ... transforming a raster file to GTIFF with the option -of COG already performs a transformation to a basic Cloud Optimize GeoTIFF with internal tiling and compression parameters. The gdalwarp page provides more options to even optimize further.
Styling Raster data
Some categorized raster datasets come with no data values. While styling a raster dataset with NoData Values, make sure to use the type: ramp, even when it is categorized data. for type:value, trying to style a NaN does not work.
Vector formats
While it may seem like a straightforward issue, optimizing data input in GeoServer can be complex due to the multiple formats supported and the various pathways to optimization. However, one combination that consistently yields the best performance is the use of PostgreSQL/PostGIS in conjunction with GeoServer. PostGIS, in particular, offers several powerful tools to optimize the data experience, with PostGIS Spatial Indexing and Primary Keys being the most notable. By leveraging these indexes and keys, users can significantly improve the efficiency and speed of their data delivery. Setting up these indexes and keys is a relatively straightforward process, but it does require access to a PostgreSQL/PostGIS database and a certain level of technical expertise. Although PostgreSQL/PostGIS is a standard tool provided by Deltares IT (see topdesk link, can only be used by Deltares employees), its steep learning curve can present a barrier to entry for some users, making it essential to invest time and effort into mastering its capabilities. But this will pay off! Especially if datasets are dynamic and/or big.
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