Hello,
I am not clear on how you have determined the speed, i.e while backups 
running & cloning ongoing  ?
How is your backup enviroment configured, do you have any existing storage 
node, what is the performance of this SN servers when cloning ? Please 
give us more information before any one can make recomendation.
If you are CDL user SN licence may be a good option to have.

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