Configuration Performance factors
Backup performance can be influenced by your hardware environment as well as settings in SQL Server, the NetBackup master server, and NetBackup for SQL Server. This section discusses the most prominent factors in SQL Server and NetBackup for SQL Server. The availability of buffer space has a definite influence on how fast backups run.
Buffer space parameters
There are three parameters you can use to increase buffer space in SQL Server.
The MAXTRANSFERSIZE parameter can be set for each backup or restore operation. It ranges in size from 64 kilobytes to 4 M bytes. The default is 64 kilobytes. MAXTRANSFERSIZE is the buffer size used by SQL Server for reading and writing backup images. Generally, you can get better SQL Server performance by using a larger value.
Set the MAXTRANSFERSIZE for your NetBackup for SQL Server session by choosing File > Set NetBackup client properties or add this parameter to batch file. For more details on the MAXTRANSFERSIZE parameter, see “Overview of batch files” on page 105.
The BLOCKSIZE parameter can be set for each backup operation. For restores, NetBackup for SQL Server automatically chooses the same size that you backed up with. BLOCKSIZE ranges from 512 bytes to 64 kilobytes. The default is 512 bytes. BLOCKSIZE is the incremental size that SQL Server uses for reading and writing backup images.
Set the BLOCKSIZE for your NetBackup for SQL Server session using the NetBackup client properties dialog box. Otherwise, you can use the BLOCKSIZE parameter to set this value when you create a batch file manually. For more details on the BLOCKSIZE parameter, see “Overview of batch files” on page 105.
NUMBER OF BUFFERS PER STRIPE
The NUMBER OF BUFFERS PER STRIPE parameter affects buffer space availability. This parameter is set in the NetBackup MS SQL Client interface for each operation. NetBackup uses this parameter to decide how many buffers to allocate for reading or writing each data stream during a backup or restore operation. By allocating a greater number of buffers, you can affect how quickly NetBackup can send data to the NetBackup master server.