Whenever I heard about Amazon using SOA heavily, I thought this is how they implemented it (making HTTP requests to
their own API). Is it true? If there is a performance penalty to this approach, what are the alternatives to call the internal services/APIs? People talk about services all the time, but no one talks about the actual implementation. Thanks to the blog author for documenting this. It would be great if someone could point out similar articles.
My understanding of Amazon's internal SOA usage is that it is geared toward timeout-enforced service response guarantees to mitigate concerns about performance penalty. Specifically, a page render event triggers initiation of asynchronous calls to N service endpoints( I have read as many as 300 per page render event ). The page renderer will wait for a specified time to receive responses from each service, but timeout on those services that do not meet their latency SLA. Page components with dependencies on either error result or timed-out service responses will simply be not rendered or replaced with dummy content.
Employees of Amazon, feel free to correct any holes or errors in my understanding of the web application architecture there.
