Storage Engine Metrics
----------------------

| name | type | description  |
|---|---|---|
| metric.lsn | int | Current log sequential number. |
| metric.tsn | int | Current transaction sequential number. |
| metric.nsn | int | Current node sequential number. |
| metric.dsn | int | Current database sequential number. |
| metric.bsn | int | Current backup sequential number. |
| metric.lfsn | int | Current log file sequential number. |