MSDP Restore performance drops on NetBackup instance hosted on a Flex Appliance after upgrading instance to version 8.2

Problem

After upgrading an existing NetBackup application instance with MSDP storage to version 8.2 on a Flex Appliance, the instance experiences a decrease in restore performance.

Note: This issue only occurs if you downloaded the 8.2 application before October 1, 2019 and used it to create or upgrade an instance. A new 8.2-1 version was posted after that date that includes the fix to this issue. Veritas recommends that you refresh all 8.2 instances with the new 8.2-1 version. However, you must still perform this procedure to resolve the issue even if you refresh your instance.
See How to repair a NetBackup 8.2 application instance.

Cause

For best performance, the WriteThreadNum value in in the MSDP contentrouter.cfg file is set to 1 on all MSDP application instances. However, during an upgrade to version 8.2, the WriteThreadNum value gets changed from 1 to 2.

Solution

To change the WriteThreadNum value back to 1:

1. Open an SSH session to the application instance after you have upgraded it to version 8.2.
2. Run the following commands:
   1. sudo /usr/openv/pdde/pdag/bin/pdcfg --write=/mnt/msdp/vol0/etc/puredisk/contentrouter.cfg --section=CRDataStore --option=WriteThreadNum --value=1
   2. sudo /etc/init.d/pdde-storage force-stop
   3. sudo /etc/init.d/pdde-storage start