Start/notes.ini Parameters/NSF_DbCache_Disable

NSF_DbCache_Disable

🛠️
Parameter: NSF_DbCache_Disable
Short description: Disables the NSF database cache completely – set only for debugging or in case of cache-related corruption, because performance drops drastically.

Profile

Parameter
NSF_DbCache_Disable
Category
Performance / Memory
Component
Server
Available since
10.0
Supported versions
10.0, 11.0, 12.0, 14.0, 14.5, 14.5.1
GUI equivalent
notes.ini only (no GUI)
Possible values
0 = cache active (default), 1 = disable cache

Description

⚠️
HCL explicitly does NOT recommend this notes.ini switch. Per HCL admn_dbcachedisable_r and tune_managingthedatabasecache_t: "Using a NOTES.INI setting to disable the database cache, as opposed to using the server command, is not recommended." Use the server command Dbcache Disable at runtime instead.
The NSF database cache keeps frequently accessed databases open in order to save open / close overhead. In very rare cases (cache corruption, diagnosing lock issues), NSF_DbCache_Disable=1 helps to switch the cache off completely and observe behavior without it.
In production, however, this leads to noticeable performance loss and higher I/O load – so use only as a diagnostic tool.

Example configuration

NSF_DbCache_Disable=1

Notes & pitfalls

  • Never enable permanently in production.
  • If the cache must be turned off: HCL recommends the server command Dbcache Disable instead of the notes.ini switch.
  • Pairs with NSF_DbCache_MaxEntries, NSF_DbCache_DropTimeout.
  • Current cache status visible via show stat database.dbcache.*.
  • For suspected corruption, try dbcache flush as an alternative.
  • The change takes effect after a server restart.