It's the people who thought Ethernet Pause was ever a good idea.
I've only seen it lead to tears. In all of the situations I've run into, it would be better to drop packets that are arriving too fast to handle than to try to fix it up by trying to do flow control. Ethernet is unreliable, and packet loss is the overload signal; PAUSE changes overload from drop to buffer, and then you end up with problems with overlarge buffers. In addition to things like where a multi-queue nic has one queue overloaded and sends PAUSE, which results in starvation for the other queues; or PAUSE getting broadcast over a switch when it shouldn't have been, etc.
Comments
It's the people who thought Ethernet Pause was ever a good idea.
I've only seen it lead to tears. In all of the situations I've run into, it would be better to drop packets that are arriving too fast to handle than to try to fix it up by trying to do flow control. Ethernet is unreliable, and packet loss is the overload signal; PAUSE changes overload from drop to buffer, and then you end up with problems with overlarge buffers. In addition to things like where a multi-queue nic has one queue overloaded and sends PAUSE, which results in starvation for the other queues; or PAUSE getting broadcast over a switch when it shouldn't have been, etc.