In provider_client.go, it sets http request Close option to true to close the connection after replying to the request.

// Set connection parameter to close the connection immediately when we've got the response
req.Close = true

It makes the connection cannot be reused, and every request requires to establish a new TCP connection. Not only does the latency increase, but also increase the overhead of both gophercloud clients and openstack services.

Furthermore, there are several requests do not close the response body after sending the request. It also makes the connections cannot be reused even after the Close option is set to false.