On Mon, Jul 25, 2011 at 3:17 PM, Allen Wittenauer <[email protected]> wrote: > > On Jul 25, 2011, at 11:59 AM, Eli Collins wrote: >> Note! MR2 supports the current job >> API - users don't need to rewrite their jobs to run on MR2 - this is >> about the MR *implementation* not job compatibility. Note that the >> move to MR2 will affect some APIs (eg metrics, contrib projects that >> only work against MR1, etc). > > Don't forget that this completely breaks operations, as in our entire > world is about to get blown apart and it will take us quite a while to > recover. >
Yes, moving operations from MR1 to MR2 will require some work. >> The current MR1 implementation will of >> course remain supported in the current stable releases. >> >> Rationale: there's a lot of cost but little gain to maintaining three >> MR implementations. > > What are the three implementations? I only see two? > 1. MR1 in stable 2. MR1 in trunk 3. MR2 in trunk Given that we only recommend #1 and #3 it doesn't make sense to support #2. Thanks, Eli
