Amazon Sandbox (Product Advertising) - HTTP 503 Errors and Request Throttling

I use Amazon's Product Advertising API to retrieve their node hierarchy using the API's BrowseNodeLookup method (REST using Java). On Amazon's sandbox individual requests seem to work but if I keep sending requests for various nodes I eventually end up getting HTTP 503 errors.

One of previous posts on an Amazon's forum indicated a lim开发者_StackOverflow中文版it of 20 requests per second on sandbox: https://forums.aws.amazon.com/thread.jspa?messageID=152657𥑑

After I put throttling in place I tried limiting code to send 20 requests/sec, as well as 10 requests/sec. In both cases I ended up eventually getting a 503 error. I had posted my question on Amazon's forum but have not received any information so I was wondering whether anybody knows answers to the following questions:

1. What kind of limits does the sandbox environment impose in this case?

2. Are those or similar limits in place in the production environment?

3. Do those limits apply to both REST and SOAP calls?

Maybe 10 requests/sec is too many?

I am having the same problem. I found this link that mentions 1 request/sec.

http://www.mail-archive.com/google-appengine@googlegroups.com/msg19305.html

It's approximately 2,000 per hour; with the opportunity to scale up if you're a merchant shipping a lot of product sold through their marketplace.

One way to help with this limit is by batching multiple requests in each API call - they're treated as one invocation, for the purposes of Amazon's rate-limiting governor. Not only does that help with throughput by permitting larger sets of requests to be issued; but because you're not dealing with intermachine latency (between your app & the Amazon server handling your API request) you're making up a bunch of time there, as well.