From the release page on hadoop’s website:
“This release, like previous releases in hadoop-2.x series is still considered alpha primarily since some of APIs aren't fully-baked and we expect some churn in future.”
How “alpha” is the 2.x line? We’re moving off AWS (1.0.3) onto our own cluster of 10 servers, naturally we want the latest and greatest, but don’t need to live on the bleeding edge (we just wanna process some data, you know!).
So how “Alpha” is “alpha”?