Resolution: Won't Fix
Affects Version/s: 2.2.0
Fix Version/s: None
Rebuilding write pipelines is expensive and this can happen many times during a rolling restart of datanodes (i.e. during a rolling upgrade). It seems like it might help if datanodes could be told to drain current work while rejecting new requests - possibly with a new response indicating the node is temporarily unavailable (it's not broken, it's just going through a maintenance phase where it shouldn't accept new work).
Waiting just a few seconds is normally enough to clear up a good percentage of the open requests without error, thus reducing the overhead associated with restarting lots of datanodes in rapid succession.
Obviously would need a timeout to make sure the datanode doesn't wait forever.
|Transition||Time In Source Status||Execution Times||Last Executer||Last Execution Date|
|99d 5h 16m||1||Kihwal Lee||07/Feb/14 23:09|
|Status||Open [ 1 ]||Resolved [ 5 ]|
|Resolution||Won't Fix [ 2 ]|