Email Subscription Notifications Suspended Temporarily
We are in the process of making navigation in the Servers and Operating Systems forums simpler and more direct. While doing this, we have to temporarily suspend email notifications for subscriptions. If you are subscribed to one or more discussion boards or blogs in the community, please check them daily to see new content. Notifications will be turned back on in a few days. We apologize for any inconvenience this may cause. Thanks, Warren_Admin
StoreEver Tape Storage
cancel
Showing results for 
Search instead for 
Did you mean: 

ultrium 230 on l2000

Haim Fridman
Occasional Contributor

ultrium 230 on l2000

We have purchaed an ultrium 230 tape drive and connected it to L2000 via the ultra wide scsi2 interface that is on the core io board together with the nic.
We have tried to backup 140G
of data with tar and with ftio but only 100G backed up
with transfer rate of 13m/sec.
I understand that lto 230 shud backup up to 200g with transfer rate of 30m/sec .
Why it isn't so on my system?
3 REPLIES
Eugeny Brychkov
Honored Contributor

Re: ultrium 230 on l2000

Hi,
native data transfer speed is 15mb/s, but with compression ratio 2:1 it can be 30mb/s.
So, please check if you backing you data up with compression turned on. In addition, for optimal perfomance and long life of drive it is recommended that throughtput to be at least 15mb/s (for Ult230 and 7,5 for Ult215). Please check SCSI bus for errors and PDC for bus speed setup to be 'unlimited'
If you have compression turned off right now I would tell that perfomance is not bad. Tune system to raise perfomance to at least 15mb/s.
Eugeny
Leif Halvarsson_2
Honored Contributor

Re: ultrium 230 on l2000

Hi

Tar and perhaps not ftio is not fast enough to stream a LTO drive at full speed. You need a high performance backup program (for examplse OmniBack).

Check the data you backup. Don't expect high performance if backing up millions of small files (unless with disk image backup).

Check compression ratio of your data, use "compress" command on some typical files. Compress uses the same algorithm (LZW) as the drive. You need at least 2-1 ratio to get 30MB/s.

Disk/filesystem performance. You need a very fast disk system to stream a LTO drive. With OmniBack (or other high end products) you can back up several filesystems in paralell to one drive.

You should read the document "How to optimize performance of HP Ultrium tape drives".

http://www.hp.com/products1/storage/products/tapebackup/ultrium_tapedrives/ultrium230/infolibrary/whitepapers/ultperfpress.pdf
Haim Fridman
Occasional Contributor

Re: ultrium 230 on l2000

Hi

1. How can i check if the compression is turned on ?

2. How can i check the scsi bus and set the PDC bus speed to unlimitedt?