whatever that makes the IO believe that you dont have intention to live permanently in the US will lead him to forfeit your green card. Leaving the US for longer than a year is just one of many ways to give such an intention that you don't want to live permanently in the US. If you leave the US for more than 180 days and less than 365 days, you should try to convince IO that you still want to live in the US forever.
if you don't plan to travel the same amount next year, should be fine. At most a warning for now. If you do the same next year, you probably will get a firm warning.