GD read (download) speed of normal mount vs cache mount

I just finished configuring the new cache feature with my Google Drive and I notice quite a large disparity in bandwidth if I rsync a file from my normal GD mount vs my cached GD mount.
With the normal mount I get ~18MB/s (my max connection speed) while if I try to rsync the same file from my cache mount I only get ~4.8MB/s. What could cause this huge difference in performance?

I use the default values for cache options.

Cache is chopping the file in chunks and caches them locally as well. It isn’t ideal for direct reading I believe. The advantage it gives is that on a second read you’ll essentially read from the local cache rather than GD.

I’m not sure about the performance part of it and never did a comparison between a direct read and a cached one so I can’t say if the difference is expected. Perhaps someone else can talk about it.

It seems experimenting with cache-chunk-size (default 5M) improves the transfer speed. I set it to 50MB and I get 11-15MB/s. Will keep testing.

It makes sense as it will increase the chunk size and lower the times it has to store in cache (db and disk data).