I just measured it and at about 60 Mbps the CPU load was 100% and about the half of this usage was queuing so this CPU speed is simply not enough for such bandwidth.if you have RB450G still in place, you can try by reducing cpu speed to 400MHz that will be the same as RB7501G regarding speed.
And how much is the speed drop if I use queue trees (+many firewall mangle rules) for QoS purposes?we have not tested exactly that, but you can try. After all it has around 370Mbps throughput with firewall/conntrack and routing
swtich is wirespeed.
Sorry for the late response. The problem is found and we are working to fix it.
I can confirm that supout generation and console is working again. Bug report was sent with the support file.Please upgrade to v5.2 and test again. It contains fix for supout.rif generation as well.