It is recommended to use CPUs designed to support Advanced Encryption Standard Instruction Set (or the Intel Advanced Encryption Standard New Instructions (AES-NI) to improve performance.

You can use the following command to verify whether or not the processor supports encryption acceleration:

$ grep -o aes /proc/cpuinfo   
aes 
aes 
aes 
aes

If the command does not produce any output, the processor does not support encryption acceleration.