Replication statistics

Answer

Historically, concern has been expressed when certain Tivoli Storage Manager commands are issued, the server would appear to "sit there/hang" for a long time without indicating a change, then it would start reporting progress. With replication, this is addressed by overlapping the "decision" phase with the "movement" phase. As the server is examining files in the file space to determine which files need to be replicated (or updated or deleted), the server will generate batches of work to do. Once the server fills a batch, the server will start processing that batch, even though the server has not finished looking at all the files in all the file spaces.

Looking at the Query Process output (sample below), we report file spaces as being in one of 4 states:

1) Identifying: means the server is still looking at the objects in the file space and have not yet dispatched any batches for replication.
2) Identifying and Replicating: means the server is still looking at the objects (Identifying) but is also moving objects (Replicating).
3) Replicating: means the server is done looking at the objects (in the file space), and the values you've seen increase will stop increasing.
4) Complete: means the server finished the file space.

When replicating multiple nodes or file spaces, the numbers to process may change as long as any file space is still in an "Identifying" phase. Once they are all "Replicating" or "Complete", then you know the server has looked at everything.

In the sample Query Process output, it shows 2408 file spaces not yet started. In this case the numbers in the various states will continue to change for a while.

Sample: Query Proc>
5     Replicate Node      Replicating Node(s) Node 1, Node2, Node3...
                          ... File spaces complete: 229. File spaces identifying
                          and replicating: 50. File spaces replicating: 4.
                          File spaces not started: 2408. Files current:
                          381,290. Files replicated: 1,297 or 8,329. Files
                          updated: 25,577 of 176,081. Files deleted: 2,239
                          of 2,239. Amount replicated: 3,252 MB of 13,114
                          MB. Amount transferred: 1,079 MB. Elapsed time:
                          0 Day(s), 0 Hours(s), 53 Minute(s).