How to improve VMware backup performance for Backup Exec 2010 R3 and 2012.
|Article:TECH185691|||||Created: 2012-04-03|||||Updated: 2013-09-19|||||Article URL http://www.symantec.com/docs/TECH185691|
Hotfix 176937 for Backup Exec 2010 R3 improved the performance of VMWare related backup jobs. The improvement is seen with SAN transport mode and a slight improvement can be seen with NBD. With this improvement there are 8 registry keys that have been added and can be modified to get optimal performance.
Registry Keys and Location:
HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Backup Exec For Windows\Backup
"Enable Buffered Reads"=dword:00000001
"Number of Read Buffers"=dword:00000004
"Size of Read Buffers"=dword:00000400
"Enable Buffered Writes"=dword:00000001
"Number of Write Buffers"=dword:00000004
"Size of Write Buffers"=dword:00000400
"Write Thread Priority"=dword:00000000
"Read Thread Priority"=dword:00000000
Note: The perfomance improvements are still limited to the speed of your hardware and network traffic/congestion at the time of the backup.
The following registry keys can be modified to improve performance based on the configuration and setup of the media server. If the Media server has 8 CPU's and 12GB of memory then these values might be increased to see optimal performance. If the Media server has 2 CPU's and 4GB of memory then these values might need to be decreased to see optimal performance.
"Number of Read Buffers" and "Number of Write Buffers" can be increase to allow for additional buffers during the backup. The default value is 4 and can be increased or decreased by increments of 2.
"Size of Read Buffers" and "Size of Write Buffers" can be increased to allow for a larger buffer during the backup. The default value is Hexadecimal 400 and can be increased or decreased by increments of 200.
AVVI: More than 50% decrease in throughput rate of SAN based backups post SP1
Article URL http://www.symantec.com/docs/TECH185691