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Multistreams pegging out CPU

I currently have a server that I am trying to backup using multistream due to the fact the server contains over 17 million little files and this cuts the backup time from over 50 hours to around 15. Anyways at times the CPU will be pegged at 100% and the main offenders are several bpbkar32 processes. Is there a way to limit this at all? We are currently on 5.1. Thanks in advance.
2 Replies

Re: Multistreams pegging out CPU

Try a better solution. Netbackup is predicated on filenames and is not suited to be used for backing up millions of small files through regular netbackup means even if using multistreaming. Please read this technote.
 
DOCUMENTATION: How to configure backup for maximum throughput when a volume or folder contains millions of small files.
 
When a volume contains millions of small files, backup throughput may commonly drop below 1MB/sec. This is normal behavior due to the overhead of file requests that must be made to the operating system.

In this scenario, FlashBackup is recommended for maximum throughput while maintaining the ability to restore individual files.

If FlashBackup is not an option, a Windows 2000 client with VERITAS Snapshot Provider (VSP) (or Windows 2003 with VSP or Volume Shadow copy service (VSS)) can be configured to perform raw partition backups using a snapshot. This will allow the volume to be accessed while a backup is running, but give the performance of a raw partition backup.

However, there is no ability to restore individual files. In order to restore individual files from this volume, the entire volume must be restored, and then the files can be copied to where they are needed. The restore can also be redirected to a new or blank volume that is available for overwrite by the restore. The assumption is that due to the number and type of files, these files are likely to only be restored in a disaster recovery situation.
...and there is more info if you follow the link you can read the entire technote.
 
 

Re: Multistreams pegging out CPU

There's no way to throttle the CPU the bpbkar processes are allowed to consume.  Might want to drop your multistream limit by one or two if the CPU being pegged is a problem.