SAP with Microsoft SQL Server 2005: Best Practices for High Availability, Maximum Performance, and Scalability43
The priority boost option defines the priority of SQL Server processes. Having the value set to 1 gives SQL Server processes a slightly higher priority. The current recommendation is to set the priority boost option to 0, which leaves SQL Server processes with a normal priority.
In the past, SAP and Microsoft recommended setting the priority boost option to 1. However, this recommendation was recently changed. They now recommend setting the priority boost parameter set to 0. This is because of situations where operating system network threads were starved in favor of the SQL Server process, thereby causing failure situations and transaction rollbacks.
In addition, because of improvements in SQL Server 2005 and Windows Server 2003, the advantages formerly achieved by increasing the priority of SQL Server processes have been minimized.
recovery interval (min)
The recovery interval option controls the checkpoint interval, as seen in Figure 17. SAP recommends using the default setting of 0. In customer scenarios, using 0 causes a checkpoint interval to occur every 30 to 60 seconds in situations where no other event triggered a checkpoint (such as a Commit statement triggering a checkpoint).
SQL Server checkpoint intervals are extremely sensitive with disk resources. SQL Server works to avoid overloading the I/O during checkpoint writes. In the past, there have been no customer issues with I/O flooding caused by SQL Server checkpoints.
In contrast to competitor databases, the mySAP space does not require this value to be adjusted to achieve better control of checkpoint effects.
Microsoft Corporation © 2005