Imagine a system with insufficient memory to hold all data in entry and database caches. In this case, avoid causing combined entry and database cache sizes to exceed the available physical memory. This might result in heavy virtual memory paging that could bring the system to a virtual halt.
For small systems, start benchmarking by devoting available memory to entry cache and database caches, with sizes no less than 100 Mbytes each. Try disabling the file system cache by mounting Solaris UFS file systems with the -o forcedirectio option of the mount_ufs command. For more information, see the mount_ufs(1M) man page. Disabling file system cache can prevent the file system cache from using memory needed by Directory Server.
For large Directory Servers running on large machines, maximize the file system cache and reduce the database cache. Verify and correct assumptions through empirical testing.