Server idling timeout bug

I am not very sure about this but me and some friends were playing on my server and i saw this new option idling timeout and i set it to 100 I think.
Well when my friends wanted to join they got kicked after a view seconds because: End of stream
Even if I set it back to 0 it didn't worked very well and the work load was also very high. It only helped that I deletes the server.properties