Updated Optimization (markdown)

Optimization.md

@@ -29,6 +29,12 @@ curl http://localhost:9333/vol/grow?count=12&replication=001
 
 This will assign 12 volumes with 001 replication. Since 001 replication means 2 copies for the same data, this will actually consumes 24 physical volumes.
 
+The volume can be pre-created with other parameters:
+```bash	
+curl http://localhost:9333/vol/grow?count=12&collection=benchmark
+curl http://localhost:9333/vol/grow?count=12&dataCenter=dc1
+```
+
 ## Increase concurrent reads
 
 Same as above, more volumes will increase read concurrency.