The following table lists and describes migration job metrics for Database Migration Service.
Represents how many bytes the destination database is behind the
source database. Use this metric when considering performing a promotion of a
continuous migration. Replication delay should be zero at the time of
the promotion in order to avoid data loss. Note this metric is only
relevant in the CDC phase. For more information on job promotion, see
Reflects how many GB are currently being used by the destination
Cloud SQL instance. Use this metric to get a rough indication
of migration job progress.