I was at Yahoo during the time of Hadoop/MapReduce. I'd summarize the value of MapReduce in one sentence as: a solution you can use is infinitely better than a

I was at Yahoo during the time of Hadoop/MapReduce. I'd summarize the value of MapReduce in one sentence as: a solution you can use is infinitely better than a solution you can't. An optimized DB might bo much better for a specific workload. To get an optimized DB would take 6 months of conversations with a half dozen teams and getting approval for hardware. Then you'd use it for a few days before moving to your new workload. Then get yelled t for the waste of resources. To use MapReduce you logged into a cluster and ran your code the same day. MapReduce wasn't replacing databases. It was replacing local scripts running on database dumps and dozen machine clusters cobbled together to improve throughput. It's clear from the backgrounds of the people who wrote that piece that they never had to be in the shoes of the people actually using MapReduce on a daily basis and getting value from it. edit: This is a roughly the same reason cloud took off. Cloud costs more but waiting 6 months for IT to deploy a half-bake compromise solution is significantly more expensive for the business in lost opportunity and productivity.