Unclear Google Analytics API quota restrictions

Question

I've been recently fixing my application that apparently reached some GA quota limitations and I've found a couple of things that were not clear to me:

• Does the 4 concurrent requests limitation apply per application, per web property or anything else?
• If we break the 10 requests in any given 1-second period or 4 concurrent requests limitation, how long does it take before GA stops responding with 503 ServiceUnavailable error?
• Does quota per application refer to the application name string only? We are running two different web application using different GA application string. Both apps connect GA API from the same IP address. Can we expect the quota per application is calculated for each application string separately in this case?
• Are the status codes sent with 503 ServiceUnavailable response documented anywhere? Can we be sure that rateLimitExceeded refers to the 10 requests per second limitation? How can I found out the cause of an 503 response?

Btw is it possible that a stronger quota restrictions than documented may take effect sometimes?

For example, is it possible that GA replies with 503 ServiceUnavailable response just after 6 fast but subsequent requests or just because of any other undesired behavior of a client application that's not included in the documentation?

Regards,

Pavel

Answer 1

It's just been answered by Nick in the GA Google Group.

Main points: the 10 qps and 4 parallel requests limitation count per IP, even an application running on a different machine in the same network may be counted.

I've submitted a documentation bugreport to the GData issue tracker.