The SQL Server will automatically allocate, at a minimum, the amount of memory set in this configuration setting. The default 'min memory per query' option is equal to 1024 Kb.
This option specifies the maximum number of outstanding asynchronous disk I/O requests that the entire server can issue against a file. By the way, the 'max async IO' SQL Server option is no longer supported in SQL Server 2000.
This option can improve performance on networks whose base topology supports larger packets than TCP/IP's default of 4096 bytes. For example, if client sends or receives large amounts of data, a larger packet size can improve performance, because it results in fewer network reads and writes. The default value for the 'network packet size' option is 4096 bytes. Microsoft does not recommend changing this option, because for most applications, the default packet size of 4096 bytes is best.
The 'fill factor' option specifies how full SQL Server will make each index page. When there is no free space to insert new row on the index page, SQL Server will create new index page and transfer some rows from the previous page to the new one. This operation is called page splits. You can reduce the number of page splits by setting the appropriate fill factor option to reserve free space on each index page. The fill factor is a value from 1 through 100 that specifies the percentage of the index page to be left empty. The default value for fill factor is 0. It is treated similarly to a fill factor value of 100, the difference in that SQL Server leaves some space within the upper level of the index tree for FILLFACTOR = 0. The fill factor percentage is used only at the time the index is created. If the table contains read-only data (or data that very rarely changed), you can set the 'fill factor' option to 100. When the table's data modified very often, you can decrease the 'fill factor' option to 70 percent, for example.
The 'recovery interval' option specifies the maximum number of minutes per database that SQL Server needs to complete its recovery procedures. The default value of this option is 0. It means that SQL Server will automatically configure this option. SQL Server issues a checkpoint using the 'recovery interval' option. Microsoft does not recommend changing this option in general case, but sometimes you can improve performance by changing this option. You can monitor disk-write activity on the data files, and if you see periodic spikes that send disk utilization to 100 percent, you can increase the recovery interval. In this case, Microsoft suggests setting the 'recovery interval' option to 5 and continuing monitoring.
You can set this option to 1, if you want from SQL Server to work with a higher priority than other processes on the same computer. The default value is 0. Setting 'priority boost' to 1 can degrade the performance of other applications running on the same computer with SQL Server. So, you should set the 'priority boost' SQL Server options to 1 only if you have dedicated server to SQL Server. In other case, do not change this option.
The default setting for the 'max worker threads' option is 255. If the number of user connections will be less than the 'max worker threads' value, a separate operating system thread will be created for each client connection, but if the number of user connections will exceed this value the thread pooling will be used. For example, if the maximum number of the user connections to your SQL Server box is equal to 50, you can set the 'max worker threads' options to 50, this frees up resources for SQL Server to use elsewhere. If the maximum number of the user connections to your SQL Server box is equal to 500, you can set the 'max worker threads' options to 500, this can improve SQL Server performance because thread pooling will not be used.
These options can be used to specify the fixed amount of memory to allocate to SQL Server. In this case, you should set the 'min server memory' and 'max server memory' to the same value (equal to the maximum amount of physical memory that SQL Server will use), and set the 'set working set size' SQL Server option to 1. This can improve performance because SQL Server will not dynamically allocate memory. You can also change these options when SQL Server works on the same computer with other applications. In this case, the 'min server memory' options is used to allow SQL Server works when other applications pretend to use all available memory, and the 'max server memory' options is used to allow other applications work when SQL Server tried to use all available resources.
Unlike SQL Server 6.5, SQL Server 7.0/2000 can automatically allocate memory (can take more memory if SQL Server need it, and can give memory back to operation system). This is one of the main advantages in comparison with previous versions, but dynamic memory allocation takes some time. If you know the maximum amount of physical memory that SQL Server will use, you can specify this amount by setting 'min server memory' and 'max server memory' to the same value (equal to the maximum amount of physical memory that SQL Server will use) and set the 'set working set size' option to 1.
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