On Wed, Feb 20, 2013 at 3:01 PM, Tsz Wo Sze <szets...@yahoo.com> wrote: > Also, the patch seems to have removed the existing short-circuit read feature > (HDFS-2246). It is an incompatible change. I think the patch is farther > away from being ready and I would keep my -1.
The existing short circuit feature is insecure and was always considered a stop-gap solution. If you read the history of that feature, you can find comments like https://issues.apache.org/jira/browse/HDFS-4476 where I pointed out that it's only a stop-gap solution and the only reason I didn't veto is that folks agreed to later replace it with the proper solution (HDFS-347). Given that the API is the same, and this is an implementation detail, it is not incompatible. There is no reason to keep the old implementation around: it is both slower and unusable in the vast majority of clusters, where the data directories are owned by an HDFS user, and users of the cluster run under other unix credentials. -Todd -- Todd Lipcon Software Engineer, Cloudera
