Use only if your system is in a partition configuration. If not, accept the default setting (the underlying code makes a calculation based on a fixed overhead and total memory available). For information on calculating a setting for your partition system, see Optimizing server performance: Port encryption and Buffer Pool settings or the Lotusphere presentation Deploying Domino R5 for performance and scalability. NSF Buffer Pool size limits the NSF Buffer Pool size in all versions of Domino R5, up to and including 5.0.3, should not exceed 1920MB. To ensure that your settings comply with this requirement, do not set the notes.ini variable NSF_BUFFER_POOL_SIZE above the value 2013265920 and do not set the notes.ini variable NSF_BUFFER_POOL_SIZE_MB above the value 1920. In installations with more than 5GB of physical memory, at least one of these two notes.ini variables should be set, and the setting should not reserve more than 1920MB. For r5 Servers that are NOT partitioned: Domino R5 is able to scale better than Domino R4.x, allowing it to support more users concurrently. Therefore, the following parameters should not be set in the NOTES.INI file. These parameters will be automatically configured by the Domino R5 server. They will not be present in the NOTES.INI, but if left they will be supported. Also, remove any DEBUG settings within NOTES.INI. For R5 Servers that are partitioned: Unlike a standalone Domino server install, you must specify the NSF buffer pool settings for partitioned servers. On partitioned servers, the algorithm for the size of the NSF buffer pool is determined based on the amount of physical memory only, not the number of partitions that might be started. This is because that number is unknown to the server when it starts. The algorithm used to adjust the size of the NSF buffer pool hard-coded within R5 works as follows:
?1/8 of physical memory up to 32MB ?1/4 of physical memory from 32MB to 128MB ?3/8 of physical memory from 128MB to total amount
The Maximum amount for Notes 8 and 8.5 is 1024 according to http://www-10.lotus.com/ldd/dominowiki.nsf/dx/nsf_buffer_pool_size_mb allthough it is mentioned that it could reach upto 1.5 MB in size.
If you set the NSF buffer pool manually for each partition using the NSF_BUFFER_POOL_SIZE=<memory size in bytes> parameter in the NOTES.INI, the following items must be taken into consideration: ?The number of partitions ?The amount of physical RAM on the server ?How the statistics for the NSF Buffer Pool look for each partition The rule to follow is to take roughly 30% to 35% of the amount of physical RAM, and divide that value by the number of partitions on the machine. This would only be a starting point and would need to be adjusted if necessary, depending on how each partition uses Domino. To see statistics on the NSF buffer pool, run the Show statistics server console command for Database.BufferPool.Maximum.Megabytes= The peak will hit the maximum value very quickly on almost any reasonably busy server. Tip The setting NSF_BUFFER_POOL_SIZE_MB is the same as NSF_BUFFER_POOL_SIZE, but in Megabytes. If this is set, it will override any NSF_BUFFER_POOL_SIZE set. All allocated memory is used. The maximum size of the NSF buffer pool is just a limit on the amount of memory that might be allocated. It is important to distinguish between this limit and the amount of memory actually allocated. Domino will normally reach the limit. The way to determine if a buffer pool is too small relative to the buffer pools of other partitioned servers on the same machine is to compare the buffer pool hit rates. If the hit rates differ significantly, for example, 96% versus 99%, then the server with the lower hit rate needs a larger buffer pool. Caution Be very careful if you are adjusting the NSF_Buffer_Pool_Size=parameter in the NOTES.INI. If the specified value is too low or too high, it could lead to problems on the server. For more information on the Domino server upgrade from R4 to R5, refer to Moving to Notes and Domino Release 5, Lotus part number.