Forum Discussion

prats's avatar
prats
Level 4
14 years ago

Change in Netbackup buffer size

Hi,

We need to do a change in Netbackup buffer size to tune our backups.

Does it need a quiet time to implement the changes?

Guess, active backups will get affected if changes are not done during quiet time?

Thanks for all the help.

Regards

Padmaja.

7.1.x and Earlier
Backing Up
Backup and Recovery
NetBackup
Performance
  • Marianne's avatar
    Marianne
    14 years ago

    A change will not affect current backups.

    Buffer sizes are determined for each individual job before the actual data transfer is started and is used for the duration of the job. Evidence can be found in bptm log.

    New jobs that are started after the change will use the new settings.

  • Marianne's avatar
    Marianne
    Level 6
    14 years ago

    A change will not affect current backups.

    Buffer sizes are determined for each individual job before the actual data transfer is started and is used for the duration of the job. Evidence can be found in bptm log.

    New jobs that are started after the change will use the new settings.

  • Nicolai's avatar
    Nicolai
    Moderator
    14 years ago

    You can verify the buffer setting by doing a :

    findstr "io_init" {logdate}.log  for Windows

    or

    grep "io_init" {logdate}.log

    in the bptm log located in [install_paht]\netbackup\logs\bptm

    e.g:

    10:26:15.157 [4168] <2> io_init: found index: 1
    10:26:15.158 [4168] <2> io_init: using 262144 data buffer size
    10:26:15.158 [4168] <2> io_init: CINDEX 1, sched Kbytes for monitoring = 40000
    10:26:15.158 [4168] <2> io_init: using 512 data buffers

     

  • prats's avatar
    prats
    Level 4
    14 years ago

    Ok. and what about no.of buffers?

    Does this hold true for change in number of buffers as well?

     

    Regards

    prats.

  • Marianne's avatar
    Marianne
    Level 6
    14 years ago

    Correct. Check bptm log as per Nicolai's example.

    SIZE_DATA_BUFFERS :  io_init: using 262144 data buffer size 
    NUMBER_DATA_BUFFERS  : io_init: using 512 data buffers

  • prats's avatar
    prats
    Level 4
    14 years ago

    Thanks for the reply

    Changed the buffer size and active jobs were ok.

    But after changing the no.of buffers on the media server some jobs failed with status code 174 - media manager - system error occurred data buffers out of sequence,expected number 913272,received 1 and some with status code : 13 - file read failed.

    Re-runs were ok.

    Regards

    Prats.

     

  • Nicolai's avatar
    Nicolai
    Moderator
    14 years ago

    I always a good thing to do test restore before and after changing SIZE_DATA_BUFFERS - just to be sure you still can read the backups.

    Better safe now than sorry in ½  year :-D