FIND OUT WHICH PROCESS IS USING SWAP IN LINUX Posted on June 26, 2015 (February 17, 2021) by Seemab Saleem In Centos, we can easily find out which process is using the swap by using top command. For this, 1. Enter top. 2. Press O (Capital letter ‘O’). 3. Press p (Small letter ‘P’). 4. Press Enter.