Could I change redis to unix socket?

Instead of:

connectPort = PortNumber 6379

you would have:

connectPort = UnixSocket "/tmp/redis.sock"

Of course, /tmp/redis.sock should be declared in the server-side Redis configuration file using the following parameters:

unixsocket /tmp/redis.sock
unixsocketperm 755

Please note by default, unix domain socket parameters are commented out.