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  1. Home
  2. NetBackup™ Backup Planning and Performance Tuning Guide
  3. Tuning the NetBackup data transfer path
  4. NetBackup server performance in the data transfer path
  5. About the communication between NetBackup client and media server
  6. About tunable parameters reported in the bptm log
NetBackup™ Backup Planning and Performance Tuning Guide

About tunable parameters reported in the bptm log

You can use the bptm debug log file to verify that the following tunable parameters have successfully been set to the desired values. You can use these parameters and the wait and delay counter values to analyze issues.

These additional values include the following:

Data buffer size

The size of each shared data buffer can be found on a line similar to:

... io_init: using 65536 data buffer size

Number of data buffers

The number of shared data buffers may be found on a line similar to:

... io_init: using 16 data buffers

Parent/child delay values

For the duration of the parent and child delays, the values in use can be found on a line similar to:

... io_init: child delay = 10, parent delay = 15 (milliseconds)

NetBackup media server network buffer size

The Network buffer size values on the media server appear in the debug log files in lines similar to the following. The first line indicates that the NET_BUFFER_SZ touch file exists. It also indicates that bptm has tried to change the network buffer space from the operating system default. (This first line may not be present.) The second line is always present and reflects the value that the operating system uses for the current backup or restore. If the two values differ, the operating system did not allow the change to be made. You should delete the NET_BUFFER_SZ file.

The bptm child process reads from the receive network buffer during a remote backup.

...setting receive network buffer to 263168 bytes
…receive network buffer is 49640 bytes

The bptm child process writes to the network buffer during a remote restore:

...setting send network buffer to 131072 bytes
…send network buffer is 131072 bytes

See Setting the network buffer size for the NetBackup media server.

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Note on log file creation

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Example of using wait and delay counter values

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