Generally sizing of the data files is determined based on the number of objects expected to be migrated using the respective database instance. By default, the tablespaces created by MC installer totalize 60 MB. They are set to auto extend automatically when more storage space is required by MC components. There is no upper limit set. The required storage is dependent by the number of objects that will be migrated and the amount of metadata that will be scanned and imported. Roughly 75% of necessary storage is occupied by the objects metadata (source and target metadata). The rest of 25% are required by the configurations and other internal data.
To estimate the necessary storage for a migration set the following formula might be used:
Storage size = 5 * (NR_OF_OBJECTS) * (AVG_METADATA_SIZE)
NR_OF_OBJECTS – the number of objects and relations to be migrated
AVG_METADATA_SIZE – the average size in bytes of an object metadata (attribute names size + attribute values size)
Example: Migration of 800,000 documents and folders from Documentum into Documentum. The medium number of attributes was 70 and the estimated AVG_METADATA_SIZE was 5,000 bytes.
Storage size = 5 * 800,000 * 5,000 = ~20 GB.
Note: In order to be accessible from any MC client, the scanner/importer report log files are stored in MC database as CLOB fields. If big scanners or importer are run with “debugLevel=4” the size of report logs gets increased significantly and therefore additional tablespace should be taken in consideration.