10G WAN - Poor performance DEC3840

[NW4FUN]

Hello,

I've just upgraded my INET to 10G and as a result throughput has been negatively impacted. Let me explain:

INET->DEC3840->10G DAC into MS125p switch

On 1G WAN (igb0), I used to have solid 940/940 DL/UL on both iPerf3 and Speedtest.com
On 10G WAN (ax1), throughput is usually (as it fluctuates for no apparent reason) ~200M DL / ~1200M UL on both iPerf3 and Speedtest.com tested on a mGig client and ~200M DL / 940M UL on a 1G client

When running Speedtest from the OPNsense, I get a solid 6G/6G

Changing WAN (both port and speed) is the only change I've introduced and as soon as I go back to 1G on igb0, performances are back to what is expected.

Meraki TAC has been doing any sort of test and config change, this is not a SWITCH issue, I just don't know what is wrong with my FW.

Any help?

[Supermule]

Running any kind of packages??

[NW4FUN]

Yep. Tried both TCP and UDP (even worse performances on the latter)