On my website, users have files so I create a folder for each user when they register.
If site grows and I have thousands of users I might end up having too many user folders in one folder so i decided to split them up.
/userdata/1/USERID (first thousand users)
/userdata/2/USERID (second thousand users)
My questions is how much folders should I put in one subfolder? Is 1000 in each a good idea? more? less? Just want to make sure things run smoothly.