Throughput to tape

[mrfokker]

Hello

I am researching ways to increase our throughput to tape in my environment. Currently I have 2 LTO III tape drives in a Dell Powervault 132T connected through Adaptec SCSI 39160 cards. On a weekend backup I do roughly 3.75 Terrabytes in 45hrs which averages about 83G/hr. Since I am in the research phase I need a couple questions answered.


Do these numbers seem low or high for SCSI throughput to tape?

Increasing chunk size to tape icreases throughput. What kind of increased throughput would I see if I increase chunk size?

Would I benefit greatly by upgrading to fiber channel cards to the tape library? Cost versus performance. What kind of throughput would I see then.


Any help would be appreciated.

thanks

 

[theravager]

Biggest increase I made for our tape write speed was to put a spool via harddrive in front of the tape unit on fast disk with formatted with a large block size.

Most modern tape drive units can write at a scarey speed and usually the bottleneck is the server providing the data.

Theres a few things you can do with multiplexing but I've never used it being more concerned with dr recovery speed.

 

[Frbutler]

You might have to adjust infrastructure on client side to compensate for the additional speed of the fiber tape drives.

I went from scsi to fiber and ran into network issues at first.

I would get a dedicated backup network in place before you switch to fiber. It will save you some headaches later.