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16.17.1.General
When running with large data sets, one should configure the Virtuoso process to use between 2/3 to 3/5 of system RAM and to stripe storage on all available disks. See NumberOfBuffers , MaxDirtyBuffers , and Striping INI file parameters.
; default installation NumberOfBuffers = 2000 MaxDirtyBuffers = 1200
Typical sizes for the NumberOfBuffers and MaxDirtyBuffers (3/4 of NumberOfBuffers) parameters in the Virtuoso configuration file (virtuoso.ini) for various memory sizes are as follows, with each buffer consisting of 8K bytes:
Table16.19.recommended NumberOfBUffers and MaxDirtyBuffers
| System RAM | NumberOfBuffers | MaxDirtyBuffers |
|---|---|---|
| 2 GB | 170000 | 130000 |
| 4 GB | 340000 | 250000 |
| 8 GB | 680000 | 500000 |
| 16 GB | 1360000 | 1000000 |
| 32 GB | 2720000 | 2000000 |
| 48 GB | 4000000 | 3000000 |
| 64 GB | 5450000 | 4000000 |
Also, if running with a large database, setting MaxCheckpointRemap to 1/4th of the database size is recommended. This is in pages, 8K per page.