Default size of shared data buffers
The default size of shared data buffers for various NetBackup operations is shown in Table: Default size of shared data buffers.
Table: Default size of shared data buffers
NetBackup operation | Size of shared data buffers Linux/UNIX | Size of shared data buffers Windows |
|---|---|---|
Non-multiplexed backup | 64K (tape), 256K (disk) | 64K (tape), 256K (disk) |
Multiplexed backup | 64K (tape), 256K (disk) | 64K (tape), 256K (disk) |
Restore, verify, or import | same size as used for the backup | same size as used for the backup |
Duplicate | read side: same size as used for the backup write side: 64K (tape), 256K (disk) | read side: same size as used for the backup write side: 64K (tape), 256K (disk) |
NDMP backup | 64K (tape), 256K (disk) | 64K (tape), 256K (disk) |
On Windows, a single tape I/O operation is performed for each shared data buffer. Therefore, this size must not exceed the maximum block size for the tape device or operating system. For Windows systems, the maximum block size is generally 64K, although in some cases customers use a larger value successfully. For this reason, the terms "tape block size" and "shared data buffer size" are synonymous in this context.