why become so slow to run checkout branch,show diff,etc?

hello guys!

 i was happy to use idea to git my project,and found it is so well but until yesterday,it become so slow to run any git operions like checkout,merge,etc...and i have no idea why it happen and how to deal with it. As i try to get solution online,it tell me to ban runnerw64.exe which cause this problem.  but i am no sure about it.so please give me some advise.THANK YOU