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I have a COG sitting on AWS S3. The COG size is 2.3GB and is validated. I'm reading the COG into Openlayers in a standard method:

// load COG
const cogSource = new GeoTIFF({
  sources: [
      url:url,
  convertToRGB: true,
const cog = new TileLayer({
  crossOrigin: 'anonymous',
  source: cogSource,
  extent: extent,
  title: 'single'
The issue I am currently facing the load time of this COG into the browser.  It can take up to five to ten seconds to load the file. Once the COG is loaded, there is no real performance issue. Just the initial load takes a very long time.
Does anyone know if this can actually improved? Whether it be improving the headers structure of the COG or leveraging the JS in a different manner?
Site loading the COG: https://dragonfly-science.github.io/qgis-cog-tiler/
JS for the site: https://github.com/dragonfly-science/qgis-cog-tiler/blob/main/web-docs/main.js
This question may be too broad, but I need to start somewhere.
I've tried:
Using different internal tile sizes. This seems to help with the tif header size
Placing the COG behind a CDN in the hopes pre-caching might speed things up
Different compressions on the internal images. Sort of helps
I understand this my not totally be an issue specific to Openlayers, but I have found that even on my most optimized COGs, load times still lag.
                How fast is your internet connection (or your users' internet connection)?  See: How long should it take to download a 2 GB file?
– geocodezip
                Mar 9 at 4:18
        
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