I know this is an old thread but I was able to correct the pause problems on my RB260GSP's easily and wanted to share.
I was consistently experiencing pauses for 90% of 64k packets, so I would have 3mil packets with 2.6mil pauses on my VLAN Trunk ports. I found the RBs on the other end of those Trunk Ports had a default L2 MTU of 1514. After changing it to 1522 which includes the VLAN header, I have no ZERO pauses.
I hope this helps others.
that did not work for me.. i have OLT with 10G uplink sfp+ port MTU 1500 and max MTU transmission 1598 , link passes trough a CRS in switchOS mode with same vlan on crs317 ports and then connect direct to CCR1036 SFP+ port.. on CCR1036 port we have MTU 1500 and L2MTU 1598 size..
On mikrotik ccr1035 side the sfp+ port has Flow control ON on both tx and rx..
On the OLT side the flow control also enabled on the uplink 10G sfp+ port
On the CRS switch on both ports connected to OLT and CCR.. flow control disabled , max speed we can get on wifi6 devices is 250Mbps.., after we enable on both ports from CRS switch the flow control.. we can get on the next speedtest 700Mbps on wifi6 devices connected on wifi..
it works great for a couple of hours until we start seeing RX-PAUSES with hundreds of thousands in the CRS stats logs... and after few hours.. we seek internet degradation... wifi6 speeds will not go over 150mbps , after 1.5gbps traffic on the 10G uplink por from OLT --> CRS 10g port ---> ccr1036 internet uplink sfp+ port... we start seeing alot of LINK PAUSE message on the CRS port..
so i am wondering how this can be fixed? if it can be fixed at all ?
i have tried changing the interface-queues from only-hardware-queue to multi-queue-ethernet-default.. but same issue happens after a few hours..