Nigel Daley wrote:
Folks,
Some Hadoop deployments have upgraded to 0.19.0. Clearly, the 0.19
branch has issues and a 0.19.1 release is needed.
Quality issues in the changes made for the file append feature have
prevented some from deploying Hadoop 0.19. One of these changes (sync)
has now been "fixed" by reducing its semantics in Hadoop 0.18.3
(HADOOP-4997). This was necessary to stabilize the 0.18 branch.
I would like to propose that we apply this same "fix" to sync in 0.19.1
and 0.20.0. Since append requires the full semantics of sync, I propose
we also disable append (perhaps throw UnsupportedOperationException from
API?). Yes, this would unfortunately be an incompatible change between
0.19.0 and 0.19.1. We can then take the time needed to fix append
properly in 0.21.0.
I can see some people being unhappy about this, but giving them a choice
between having the filesystem work or not, hopefully they will see the
merits of the change. And I am +1 to taking time to fix things; fast
fixes often create new problems
