597d383ca4
Add sync.RWMutex to ChunkTransferStatus and lock around all field mutations in fetchAndWrite. ActiveTransfers now returns value copies under RLock so callers get immutable snapshots.
How replication works ====== All metadata changes within current cluster would be notified to a message queue. If the meta data change is from other clusters, this metadata would change would not be notified to the message queue. So active<=>active replication is possible. All metadata changes would be published as metadata changes. So all mounts listening for metadata changes will get updated.