Hello
I observed strange problem on ROS 6.15,6.17, and I dont know exactly were is the problem.
I have ROS on x86 on border router on this router I have NAT and queues based on address list
mangle looks: (for all adress-list looks the same)
;;; 30m/10m
chain=forward action=mark-connection new-connection-mark=30m/10m passthrough=yes src-address-list=30M/10M
chain=forward action=mark-connection new-connection-mark=30m/10m passthrough=yes dst-address-list=30M/10M
chain=forward action=mark-packet new-packet-mark=30m/10m-d passthrough=no in-interface=WAN1 connection-mark=30m/10m
chain=forward action=mark-packet new-packet-mark=30m/10m-u passthrough=no connection-mark=30m/10m
queue tree for mangle (for all list-tariff que tree looks the same):
name="30m/10m-d" parent=LAN packet-mark=30m/10m-d limit-at=0 queue=30md priority=8 max-limit=0 burst-limit=0 burst-threshold=0 burst-time=0s
name="30m/10m-u" parent=WAN1 packet-mark=30m/10m-u limit-at=0 queue=10m-u priority=8 max-limit=0 burst-limit=0 burst-threshold=0 burst-time=0s
interface are:
ROUT_BRZEG] /system resource> pci print
# DEVICE VENDOR NAME IRQ
0 04:00.0 Intel Corporation 82541PI Gigabit Ethernet Controller (rev: 5) 10
1 03:00.0 Intel Corporation 82574L Gigabit Network Connection (rev: 0) 7
2 02:00.0 Intel Corporation 82574L Gigabit Network Connection (rev: 0) 5
so were is the problem ? :
when I was done update ROS to 6.15 I have observed that services like (www, games, itp) has strange “delay” for example on www when I write any website address in website browser i have “connect to host…” it takes about 4-7 second delay and displays the entire website.
these symptoms are for many services 
and are best seen when traffic on router is bigger than 100Mb/s
I have done test on several different computers, on different places in network,
I was changed queue type for interface (fifo,mq, etc.)
I was done test on CCR-1016 and X86 - no different
connection speed of course is 1Gb/s on routers
I don’t have any PPPOE,PPTP connection so this is not problem with MSS/MTU
I was changed parent for queues, now each queue has parent=interface but I was create one parent queue for download for all download queues and one queue parent for upload queues ---- not resulted in any changes
the problem disappears when I do downgrade to ROS 6.10 …
I known that this is strange problem and difficult to diagnose but maybe anyone has the same problem with ROS 6.15 and 6.17 ?
the only thing that comes to mind is adding to the RouterOS flow-control to interface - maybe this add-on is broken ? …but I was tried disable and enable this function and is no different