Special considerations for large databases

Deployment options: Netezza Performance Server for Cloud Pak for Data System

If your system has large databases (that is, databases which are greater than several hundred GB in size), the default configuration settings for the Tivoli® Storage Manager server might not be sufficient to manage the backup and restores of those large databases. If the database is too large for the default configuration settings, the database backups might terminate and return errors similar to the following error:

Error: Connector exited with error: 'ANS1017E (RC-50) Session 
rejected: TCP/IP connection failure' 

The server does not have enough recovery log space to continue the 
current operation

The server does not have enough database space to continue the current 
operation
There are some configuration settings changes that can help to avoid these errors and complete the backups for large databases. These configuration settings depend on factors such as network speed, Tivoli Storage Manager server load, network load, and other factors. The following values are conservative estimates that are based on testing, but the values for your environment can be different. If you encounter errors such as timeouts and space limitations, try these conservative values and adjust them to find the right balance for your server and environment.
  • COMMTIMEOUT
    Specifies the time in seconds that the Tivoli Storage Manager server waits for an expected client response. The default is 60 seconds. You can obtain the current value of the setting by using the QUERY OPTION COMMTIMEOUT command. For large databases, consider increasing the value to 3600, 5400, or 7200 seconds to avoid timeout errors, which can occur if the complete transfer of a database does not complete within the time limit: 
    SETOPT COMMTIMEOUT 3600
  • IDLETIMEOUT
    Specifies the time in minutes that a client session can be idle before the Tivoli Storage Manager server cancels the session. The default is 15 minutes. You can obtain the current value of the setting by using the QUERY OPTION IDLETIMEOUT command. For large databases, consider setting the value to 60 minutes:
    SETOPT IDLETIMEOUT 60
  • The default size of the Tivoli Storage Manager server database, 16 MB, might be inadequate for large Netezza Performance Server databases. Depending on the size of your largest Netezza Performance Server database, you can increase the default Tivoli Storage Manager database size to a value such as 500 MB.
  • The size of the recovery log might be inadequate for large Netezza Performance Server databases or those databases that have many objects (tables, UDXs). An increased value such as 6 GB might be more appropriate. The recovery log should be at least twice the size in GB as your largest table in TB. For example, if your largest table is 2 TB, the recovery log must be at least 4 GB. In addition, you might need a larger log file if you run multiple concurrent backup jobs on the same Tivoli Storage Manager server, such as several Netezza Performance Server backups or a combination of Netezza Performance Server and other backups within the enterprise.