Defining a processing rate for an App Engine mail queue

I believe the following queue.xml represents the fastest processing rate you can configure for a Task Queue on App Engine:

<?xml version="1.0" encoding="utf-8"?>
<queue-entries>
    <queue>
       开发者_如何学运维 <name>fastest</name>
        <rate>50/s</rate>
        <bucket-size>5</bucket-size>
    </queue>
</queue-entries>

I an app were to use this queue to send out emails would it violate the App Engine rate limit for mail services?

If so, what would be a preferable configuration for a mail queue?

You should check your rate against the API limits documentation to see if you'd go over. You could certainly go over at that rate...