growing file in system volume folder

im not real shure how to explain the problem i have but will do my best and if you dont understand somthing please ask any way i have a server running win 7 amd9850 2.6ghz 8gb ram and 11.37tb storage and a 80gb hd for the os anyway i have 2 files in the system volume info folder that @ 1 time were 11gb and 25gb respectfully i called a local pc shop and the guy told me to shrink the system restore file so i did and it went back to aprox 39gb free now over the last week the free space has shrunk again so i looked @ system restore and it had reset its self for 50% when i had set it for 5% im just wondering what i can do short of turning system restore off to prevent 7 from adjusting the restore size

Do you use Avast ?
Some people have this problem with Avast.

yes i do use avast been using it for years also use it on my main rig running 8.1 pro with 0 issues

Here's a couple of Avast forum threads about this:
https://forum.avast.com/index.php?topic=162041.0
https://forum.avast.com/index.php?topic=163039.0

There may be more ...

I also use avast and also have this, just remember to set restore point to my optimum (20%) once every week, might as well get rid of avast and get avg 2015 instead.

fwiw, I have Avast free 2015 on one system and don't have this problem.
I don't have any of the optional Avast "bloat" installed (including NG).
I have System Restore turned off, I use Macrium and Acronis backup imaging.