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IBM Lotus Domino attachment and object services (DAOS) can be configured to save significant space at the file level by sharing data identified as identical between databases (applications) on the same server. Document attachments are the first components to use the DAOS feature in Lotus Domino. For more information see, IBM Lotus Domino going green: The new Lotus Domino attachment and object services.
When DAOS is enabled, the amount of disk storage being used for attachments will be reduced. It is important to note that this may also cause a significant increase in the number of integrated file system objects associated with the Domino server. An increase in the number of integrated file system objects may result in much longer save/restore times. Careful consideration should be given to the minimum attachment size for DAOS to balance the disk storage reduction and the save/restore time increases. See chapter 15 of the "IBM i Performance Capabilities Reference" for additional save/restore performance information. Use the Domino Attachment and Object Service Estimator Tool to determine how the DAOS configuration can be tuned to reduce disk storage utilization.
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