Last year, I pointed out that Amazon has a highly diversified DBMS strategy. Now Mike Vizard has a great interview with Werner Vogel, Amazon’s CTO, where he unearths a lot more detail. And it turns out that Amazon has been a hardcore adopter of DBMS2, since long before DBMS2 was named.
This is most easily seen from the interview in two aspects. One is Amazon’s extreme commitment to SOA — again, since long before SOA was named. The other is in this passage, directly about data management diversity:
Let me step back a bit. We have to kind of think about what storage means. Are we really talking about block level storage, using storage area networks or ANSCSI(?) and things like that? One important thing to realize there is that with our ownership model, we really don’t like to push off the responsibility towards a vendor for our reliability. So, no matter whether you’re using a database that is more highly available than others appear to be, whether you’re using a storage area network-in the end, it’s the application’s responsibility to be always up and running. So we never defer responsibility to the storage subsystem, for example. And we’re at Amazon, you know, using standard databases, in-memory databases, fast indices, and we’ve also built a number of storage subsystems ourselves that allow us, for example, to make the tradeoff between consistency and availability. We have some highly scalable available systems, but that now and then they give you no for an answer because you want to have them highly available. We have a number of other approaches in which we’re capable of relaxing the consistency requirements or the consistency semantics of the system such that we can always make progress under all circumstances.