Re: Restore time: LTO7 drive w/ LTO5 tape?

[DrFranken <midrange@xxxxxxxxxxxx>]

THe LTO media and drive play very little into this actually. Yes a 7 is 
faster than a 5 and by a wide margin, right about 2.5 if you want to get 
technical.

However the biggest factor will be the system you are restoring too and 
also by a wide margin.

To realize the speed of that LTO7 you needs many fast arms or many more 
not as fast arms, it really boils down to that. Heaps of memory and 
scores of CPWs will help but it's all in the ability of IBM i to get the 
data to disk and there is no substitute for I/O bandwidth for this.

How many? Can't say. If your data is 10 large save files that will 
restore orders of magnitude faster than 25 million IFS objects. But my 
best arm chair admin guess is you'd need at least dozen SSDs and on a 
current level RAID card to get close absorbing the data from that LTO7. 
Mirroring would be much better than RAID as well.

        - Larry "DrFranken" Bolhuis

www.Frankeni.com
www.iDevCloud.com - Personal Development IBM i timeshare service.
www.iInTheCloud.com - Commercial IBM i Cloud Hosting.

On 3/18/2019 8:59 AM, Justin Taylor wrote:
> If I do a backup on an LTO5 drive with LTO5 tape and it takes 10 minutes.  The general estimate is 1.5-2x for the restore (15-20 minutes).  What about if I do the restore on an LTO7 drive?
>
> I know there are a multitude of factors involved.  I'm looking for a rough estimate for restore times.  Can I still expect 15-20 minutes?  Closer to 5 minutes or an hour?
>
> TIA