TDI client low performance on loopback

Hi,

we have a TDI client driver that works fine on the real network hardware
but shows very low performance if configured on a loopback. Every send
gets approx. 200ms delay. AFAIK it’s not Nagle as it’s disabled on a
loopback and not ACK problem as we do not use “send-send-recv” logic any
more - only chained MDL send. So any ideas what can it be? Did anybody see
anything like this?

Thanks for help!

Anton Kolomyeytsev