[dev][glance_storage][s3] improving download speed from s3 backend

Hello everyone,

I did not find any option to use something like multipart downloads (only uploads) or concurrency when downloading from s3 storage. So my first question is if this is correct?

Second, I see that boto3 is being used: https://opendev.org/openstack/glance_store/src/branch/master/glance_store/_d...

and I wonder if it is possible to implement using the concurrency settings from boto: https://boto3.amazonaws.com/v1/documentation/api/latest/reference/customizat... ?

Best,

Gökhan