Poor Backup Time

[Randy Griffiths]

We have a HP Storageworks 1000 SAN and a fibre link to a HP Storageworks 1500 MSA Storage System. We use Veritas as our backup software and a full backup of 700GB is taking 24hrs and averaging 5MB/s. I think that it should be much higher and we have done a lot of testing. Even copying a file on the SAN to the SAN averages about the same rate. Is this normal are we experiencing terrible backup speeds?

[TTr]

700GB in 24 hours is 8MB/s. You should be getting a little more than that but there are more factors that affect the backups than just reading your storage. To check your storage you should perform read tests ofrom your OS, that is reading only, not copying. After you do this and you verify that you have plenty of bandwidth on the storage system, then check the other components in your backup environment. You have to follow tha path of your backup traffic. Depending on your backup environment the data tarvel might be:reading the data of the arrays, server backplane, server NIC, LAN, media server, tape SAN, tape drive(s). Any of these can affect your backup times.

[gregersenj]

If you have got a virus scanner runnning, that might have a high impact on performance.

The following link is intended for trouble shooting performance problems with tape backup, but there may be some usefull hints.

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=lpg50460

[OFC_EDM]

Also don't forget the nature of the files.

If that 700GB is full of very small files it will take a lot longer than if was full of large files.

There also may be a buffer issue causing a common problem called shoe shining. You may want to do a search on that and see if it applies to you.
- Basically instead of streaming the data to tape keeping it busy. When Shoe shining occurs the tape is doing a lot of re-positioning.

[Randy Griffiths]

It is not to tape but it is disk to disk. I estimated on the size but the backup system has an overall average of 5 MB/s in the log. Will an anti-virus on the server, not the SAN or the Disk storage affect a transfer?

[Randy Griffiths]

I have done some other testing using a 1.6GB file. I get the same speeds for SAN to Disk Backup, SAN drive to another SAN drive, and SAN to another PC. On the disk backup going from one drive to another, I get around double the speed. Am I incorrect in thinking that the SAN to SAN should be lightning fast?

[TTr]

> the SAN to SAN should be lightning fast?

Not necessarily. Again there are many factors that can affect SAN based I/O. The SAN controllers do have very high I/O rating but the backed array disks, the RAID type, number of disks in use, other concurrent I/O at the disk level and at the host level, he HBA itself, the server slot where the HBA is plugged in, the server backplane and other server I/O can affect specific SAN based I/O.

[gregersenj]

Anti virus, may have an impact on the perfomance.

When you do a copy, remember that the data is loaded into the memory of the machine, from wich you run the copy command.
So you might scan on the way in, and on the way out.

Try to use some of the tools, mentioned in the link i posted.

/jag

[JurajG]

I saw similar issues in the past with Veritas BackupExec as this can use only 1 reader for data. It is just not built for this...
Legato, Netbackup or DP can be configured to utilize multiple readers for the data being written to tape which will boost your performance.

The number of disks in MSA shelf - Nr of shelfs - number of servers on MSA - layout of LUNs - zoning - server RAM memory - CPUs - NIC's - backup aplication backup catalog - file size

All of above factors comprise to the backup performance.
some physical limitations:
####Storage controllers performance
controller___drive trans. channels__channel tranfer
SA 5300 4 528MB/s

MSA1000 [1500] - uses SA541

####Backup carrieer speeds
media speed(max) speed(typical)
FC 200MB/s->720GB/hr 500GB/hr