Bogdan Costescu wrote:
long as it fits in one page. At another time, the switch was more likely to drop large frames under high load (maybe something to do with internal memory management), so the 9000bytes frames worked most of the time while the 1500bytes ones worked all the time...
This is an important point. The way hardware flow-control works in Ethernet, a switch has to be able to buffer two full frames plus the time on the wire for the round-trip. For the curious, the PAUSEs packets are sent in-band and you cannot send or receive partial frames. So, instead of requiring ~4K per port minimum, you need about ~20K per port. Add to that up to 8 priorities with DCB and the buffering requirement are quickly getting out of hand. That's one big drawbacks of large MTUs, along with contention with wormhole switching.
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