Start/notes.ini Parameters/DAOSMinObjSize

DAOSMinObjSize

DAOSMinObjSize defines the size (in bytes) at which an attachment is offloaded from the NSF into the DAOS storage (NLO file). The parameter is the notes.ini equivalent of the field „Minimum size of object before Domino will store in DAOS“ in the Server document (tab „DAOS“).

Profile

Parameter
DAOSMinObjSize
Component
Server
Category
DAOS
Available since
Domino 8.5; currently documented in HCL Domino 9.0.x–14.5.1
Value format
Integer in bytes
Default
4096 (4 KB)
GUI equivalent
Server document → „DAOS“ → „Minimum size of object before Domino will store in DAOS“

Description

When DAOS is active on a server, Domino inspects the attachments contained in every write access to a logged database (ODS ≥ 52). If the size of an attachment is greater than or equal to the threshold defined in DAOSMinObjSize, the attachment is offloaded into an NLO file; only a DAOS reference remains in the NSF. If the attachment is below that, it stays in the NSF.

Choosing the threshold

  • Default 4096 (4 KB): proven; captures the bulk of all mail attachments (PDF, images, Office) and maximizes the deduplication gain. Risk: many small NLO files.
  • 65536 (64 KB): significantly reduces the number of NLO files; only captures attachments from 64 KB onward. Suitable when the file system shows performance issues with hundreds of thousands of NLO files.
  • 1048576 (1 MB): suitable for archive-heavy servers, where mainly large attachments should be deduplicated; minimal NLO file count.
Before activating DAOS on a productive server, HCL recommends using the tool DAOS Tune (from Domino 12.0.1, further improved in Domino 14.5) to determine the optimal threshold for the respective server based on data.

Examples

Server with default threshold (4 KB):
DAOSEnable=1
DAOSBasePath=D:\DAOS
DAOSMinObjSize=4096
DAOSDeferredDeleteInterval=30
Server with raised threshold (64 KB) to reduce the number of NLO files:
DAOSEnable=1
DAOSBasePath=D:\DAOS
DAOSMinObjSize=65536
DAOSDeferredDeleteInterval=30
Archive server that only offloads very large attachments:
DAOSEnable=1
DAOSBasePath=D:\DAOS
DAOSMinObjSize=1048576
DAOSDeferredDeleteInterval=60

Notes

  • Change takes effect prospectively – raising the threshold does not automatically pull existing NLO files back; they remain in the DAOS storage until they have no more references or until the NSF is reintegrated with compact -c -daos off.
  • Unit is bytes – not KB or MB. DAOSMinObjSize=4 would actually mean 4 bytes and would be fatal on a production server (millions of mini NLOs).
  • Companion parameters – DAOSEnable, DAOSBasePath, DAOSDeferredDeleteInterval, DAOS_ENCRYPT_NLO, DAOS_LOAD, DAOSCatalogState.

Sources (HCL Product Documentation)