If you are running OpenStack Swift Object Storage with Mastodon, to use authentication v3 you need to *not* set SWIFT_TENANT in .env.production or fog-openstack will automatically fallback to v2 if tenant is detected.

With auth v3 running you will avoid having to issue a new token for each request. Besides being best practice and probably faster (haven't tested), you will avoid token limits that OVH or others implement. Eg: I was getting 429 errors on OVH because they only allow 60/minute/user.