Q:

can I expect better than 60 milliseconds response time from google compute to google datastore

I'm measuring the latency between google cloud compute engine and google datastore. 
I'm performing a simple lookup() using the python client library.
The google performance dashboard says that my requests are consuming around 18 milliseconds. I assume that this is a server side metric and not a round trip metric.
I have added some details to my research on github.
I could not find an answer to this specific question on stackoverflow so far:
https://github.com/GoogleCloudPlatform/google-cloud-datastore/issues/5#issuecomment-72590494

A:

While Cloud Datastore does not yet provide latency guarantees, the latencies you're seeing are in line with what we've measured.
The timing information you can see in the App Engine Admin Console is computed server-side so it will not reflect the full latency of the request.
We are working on a new serving stack that should substantially reduce this latency.

