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How can the actual disk savings from DAOS be computed ?

Technote (FAQ)


The DAOS Estimator (DAOSEST) reports the expected disk savings from DAOS prior to enabling. How can an administrator determine the REAL disk savings after DAOS has been abled?


The Domino server provides the ability to report the total "logical" size of every database on server. The logical size is the size of the database including any attachments which do NOT exist in the actual mail file.

The Database -> Sizes view in log.nsf will show the total Logical size of all databases on server. You can access this view in Domino Administrator by selecting the "Server" -> "Analysis" tab. From there click on the log database. You should then be able to select the "Database" folder and "Sizes" view. A total will be listed for the entire server. This total represents the amount of space required if DAOS was not enabled.

From this total, subtract the total physical storage used by Domino to support the actual mail files plus the NLO files which support the attachments.

    Example: If the Server's mail directory is C:\notes\Data, The Windows OS provides the total space used by the directory (and subdirectories) as a folder property. If your .nlo files are stored outside of your data directory, be sure to identify the space used in that folder as well.

    Example: If the Server directory is /notes/data. iSeries Navigator can be used to review the folder properties to find this information. Alternately, the i5/OS command RTVDIRINF provides the total space used by that directory.

Subtract the total physical space from the OS command from the total Logical space reported by the Administration client. This is the TOTAL space saved by enabling DAOS on this server.

    DAOS Savings = Logical Size of all database - (Physical size of data directory + Physical size of DAOS directory, if outside of the data directory)

This is a rough guide to actual DAOS related file usage as the logical size of all databases does not include any files in the data directory that are not .nsf files. In order to be a true picture of the data saving you must look exclusively at the mail subdirectory or subtract the physical size of all files that are not .nsf files from the equation as well.

Document information

More support for: IBM Domino

Software version: 8.5, 8.5.1

Operating system(s): AIX, IBM i, Linux, Solaris, Windows, z/OS

Software edition: All Editions

Reference #: 1418283

Modified date: 18 May 2010