MORE IS NOT ALWAYS BETTER: Flow Control and Routing

[mhoppes]

Without flow control - on a flat network - performance is terrible.

[rebelwireless]

flow control anytime an interface can transmit at a higher rate than the receiving end can receive (usually wireless, like an AF5X pushing 'only' 400Mbps on a gigabit port. That transmitting gigabit port needs flow control.

Anyway, this is one reason I prefer to route everything. I know routing adds a bit of latency, and you are filling buffers, and buffer bloat, blah blah blah, but those buffers can help keep the sanity and hide or eliminate most of the waits on a mixed speed switch.

I haven't run into this too much on the wISP side as we don't push gigs out at this point, but I've had to resolve this is some high capacity enterprise networks that were planned poorly and/or had admins that just thought you plugged switches in and there was no need for experts. Funny how a VM cluster I/O collapses from switch induced waits having 10GB iSCSI storage and 1G VMs.