How common were atrocities on the Eastern Front (Nazi-Soviet) during WW2

by GSoE

Until recently I never fully grasped how massive the number of soldiers involved in this theater of the war was. It got me thinking that the war crimes I have heard so much about could have been carried out by a relatively small percentage of the troops involved in fight for the east (Germans invaded the USSR with a force of 3 million men, If .005% of these men carried out some sort of crime it would equate to 15,000 crimes. The US landed on Guadalcanal with 10,000 marines) Was this the case or did both sides as a whole commit all the infamous atrocities you hear of on an even larger scale relative to the number of troops they had.. say 15-20%.

GSoE

I hope this question makes sense