flow control settings

Can someone explain what rx-flow-control and tx-flow-control is good for?

I have an android media player that has 100Mbps interface and it has got issues. I am tweaking ethernet settings with following commands, but can’t see any difference in operation:

  1. flow-control to auto.
  2. Also auto-negotiation=none
    set [ find default-name=ether5 ] auto-negotiation=no master-port=
    ether2-master-local name=ether5-minix rx-flow-control=auto tx-flow-control=
    auto

Just google ethernet flow control or pause frames.