Galaxy S5 Lollipop Lag - Possible issue with update?

I can't find anything that explicitly states that it will wipe everything, but it looks to imply that it is in fact a factory reset. I'd like to save a factory reset as a last resort in hoping to fix this issue, unless someone specifically recommends it.
 
I know Android 5.1.1 was supposed to have patched the RAM leaks present in 5.0, but is it possible that my phone didn't patch properly?