Start/notes.ini Parameters/NSF_Buffer_Pool_Size_MB

NSF_Buffer_Pool_Size_MB

🛠️
Parameter: NSF_Buffer_Pool_Size_MB
Short description: Sets the size of the NSF buffer pool (cache for database pages) in megabytes – the most important tuning parameter for server performance.

Profile

Parameter
NSF_Buffer_Pool_Size_MB
Category
Performance / Memory
Component
Server, Client
Available since
R6
Supported versions
9.0.1, 10.0, 11.0, 12.0, 14.0, 14.5
GUI equivalent
notes.ini only (no GUI)
Possible values
Integer in MB (typically 512–8192)

Description

NSF_Buffer_Pool_Size_MB sets the size of the NSF buffer pool in megabytes – the most important tuning parameter for server performance. The buffer pool is a cache for NSF database pages; the larger it is, the more database accesses can be served from RAM instead of having to be read from disk.
64-bit Domino can size the pool significantly larger than 32-bit versions; on 64-bit, values between 1 GB and 8 GB are common.

Example configuration

NSF_Buffer_Pool_Size_MB=4096

Notes & pitfalls

  • Do not set the value larger than ½ of the physical server RAM, otherwise it competes with the OS and the HTTP JVM.
  • Without an explicit value, Domino sizes the pool automatically (often rather conservatively).
  • Effectiveness can be checked via show stat database.* (buffer pool hits / misses).
  • Specify the value in MB, not in bytes or GB.
  • For very large DBs (DAOS, mail with many replicas), tend to size it higher.