Mysql时间记录为Unixtime而不是Mysql Timestamp

I have a table with 10000 records . Each data have a time of creation. I can use PHP time() function or as Mysql Timestamp (DATETIME '0000-00-00 00:00:00'). I want to know which method increase the performance of select queries? For exampleI have a table with 10000 records . Each data h