Very poor performance

[jrc92]

I just installed 9.1 on Win2K professional. The machine has 1GB memory and an 80GB disk. When I run a backup either locally or of a remote system, I get about 350 MB/min using backup-to-disk and about 150 MB/min writing to tape. These figures seem very poor. Is this normal for BE 9.1 on Win2K professional?

During the tape backup, the number of "soft write errors" exceeded 20,000. Is this normally a software/driver problem or a hardware problem?

Thanks,
John

 

[comtec17]

Backup speeds only run as fast as the hardware can drive them. If you are backup up to disk it could be that either your controller is slow, or it is using the same disk device as your OS or App is installed on, or the disk is a RAID device.

The soft write errors using mean driver issues.

 

[jrc92]

comtec17, thanks for the info. The BE install recommended I use Veritas drivers, so I did. Are you suggesting I install the vendor (Overland) drivers?

Thanks,
John

 

[jaynichols]

in reply to comtec17 comment: just how slow is RAID-5 during backup? We don't seem to have a performance problem in our apps using these devices. All our servers are RAID-5 configured. We are only getting 89MB/min on the host server for this tape device which is an LTO backup library unit. We get that same average performance over the network.

 

[Rols]

Ok....

1) Soft Write Errors are the number of recoverable non-critical write errors that are encountered, meaning that a write operation on a block first failed and the subsequent retry was successful. They can be caused by driver problems - so upgrade your veritas driver pack, they can also be caused by tape drive & media errors.

2) Comtec is right (as usual ) The speeds are limited by your hardware. If you do a local backup to the same local disk your performance will be very poor. Copy some big files from your c: to your c: and see what kind of throughput you get - same goes with your network copy some big files over your network & see what kind of through put you get.

3) 350mb/min is quite acceptable depending on hardware. What type of tape drive (inside the overland library) are you using?? & What type of SCSI card?

Jaynicols - 89mb/min is very slow I would definatley expect more throughput from an LTO drive. I highly doubt that your RAID subsystem would be the bottleneck. It more likely to be something else - Is this a local backup or remote backup?

 

[Qdog]

When a soft-write error occurs, the tape drive is actually fast-forwarding the tape past what it thinks is a bad spot on the tape. Try cleaning the tape drive several times. If it still happens no matter what tape cartridge you use, then the tape drive is going bad, get it replaced.

What kind of hard drive is it? Sounds like IDE which would explain 350Mb/min which is normal for IDE. Try Scsi striped drives.

Comtec17 was right on the money. The backup will only go as fast as the hardware environment allows. Try NTBackup as a test. When that sucks too, you'll know it ain't Backup Exec.