I've got an RB750G on the end of a 100Mbit (licensed wireless) link. I tried a http file transfer using wget from a Linux server and obtained a fluctuating throughput of 4-8MB/sec. The CPU Load on the 750G kept hitting 99%.

When I try to perform a bandwidth test over the link (TCP receive), I can't seem to drive it over 40Mbps without the 750G hitting 99% CPU Load.

Is this the sort of performance I should expect? Are there external factors in my network that can account for the 750G using so much CPU?

Winbox 4.5

u must test it with traffic pass-throgh not making a btest directly to the device.

The original test was from a linux server using the 750G as its default gateway, downloading from a server on the other side of the wireless link.

This, to me, would be normal router operation. The question remains, why such a high CPU utilisation on the 750G?

What's your firewall ruleset? Any QoS?

There is no QOS at present and about 10 forward chain rules.

The rule allowing this data is the first rule in the forward chain.

The RB750 is NATting the linux server connection.

The rest of the firewall rules are in the input chain and from a post I saw around the place for 'hardening' the routeros.

Edit: I tell a lie, there were 3 simple queues set up. Disabling them make a 25% drop in the CPU utilisation.

Yeah, with queuing I can get just about 100Mbit through a 750G. Be really careful with excess mangling and queuing as they are big cpu hoggers.