Network – how to find the right value of MTU Jumbo frame


we take the decision to set jumbo frame on all our linux machines

we have hadoop cluster with master machines , workers machines and kafka machines

our switches ( Cisco ) are suitable to Jumbo frame and that fine

but jumbo frame can set as 8000 or 9000 or between them or less then 8000 what is the formula to calculate what is the best MTU value ?

Best Answer

  1. Make sure there's a notable performance difference between jumbos and standard frames - without it, there's little reason to dive in. Hardware offloading tends to make jumbos obsolete unless you need the final 4% throughput.
  2. You should consider your latency and QoS requirements. Jumbos increase latency and may hurt QoS.
  3. Check your equipment for the jumbo size where it's still reliable. Several devices support jumbos but behave rather poorly with them. Buffers may be too small.

The configuration of the hosts is off-topic here, unfortunately.