Problems with inference time and memory in YOLOv7

I’m testing the difference between yolov5 and yolov7 in my code but is not working as it is in the main graphic of the comparison with the real-time object detectors, the yolov7 is slower than the v5(almost the double of the time) and is using more ram too, I’m using exactly the same code of the v7 with some alterations to run inside my code ( just put the detect file in a class).
Do someone knows what could possibly is happening here? Or having the same problem? Or even maybe I’m using it wrong? Because as I said, is the exactly same code but in a class now.