HBASE-13651 I noticed that if we have a failure inside the RSRpcService.scan(), when the request has a hasNextCallSeq() the nextCallSeq is incremented and not rolledback, which means that the client retry will send a request with a nextCallSeq not up to date, which result in an OutOfOrderScannerNextException.
after the scanner heartbeat patches
HBASE-13090, we seems to be able to recover from that OutOfOrder exception, but the error show up anyway.
After a discussion with Stack we ended up saying that decrementing the callSeq on exception seems to be fine. but we had the open question about having that nextCallSeq to be atomic, if that was supposed to prevent concurrent requests with the same id. any thoughts?