Design to fail
Last night I went to an SDForum talk by two eBay architects Randy Shoup and Dan Pritchett on how they built, scaled and run their operation. The talk didn't have anything substantially different from what I've heard before, but was still impressive because they were applying some of the common thinking to their operations which runs over 15000 servers any given time. [ Slides ] Here are a few interesting phrases I took away from the talk. Scale out not up : Scaling up is not only expensive, it will also become impossible beyond a certain technical limitation. Scaling out, however is cheaper and practical. Design to fail : Every QA team I know, do a whole batch of tests to make sure all components work as they should. Rarely have I seen a team which also does testing to see whether the servers stay up if certain parts of the application fail. If you can't split it, you can't scale it : Ebay realized early on that anything which cannot be split into smaller components