Network port speed question

[philgaskin]

I have had my B3 virtually since launch and still think it's amazing. It is connected to my router's DMZ and provides a safe LAN environment on the B3's LAN port (firewalling the LAN).
I currently still only have a 2Mbps broadband connection, but hopefully will soon get 200Mbps fibre in the area. I was hoping to retain my B3 as a bridge between my DMZ and my LAN but I'm conscious of throughput restrictions through the Eth0/Eth1 bridge (Br0).
It seems that I can comfortably achieve 272 megabits per second up and down on the LAN port of my B3 but only 90 megabits per second up and down on the WAN port which also restricts the bridge throughput.
I'm connecting both ports to the same hardware which is correctly detecting 1Gbps Ethernet.
My question is whether the limitation is with the WAN hardware (Eth0) or if it is a configuration/software restriction (that could maybe be changed). Is it right there is a difference between the Eth0 and Eth1 ports?
Although I use my B3 a lot, it is mainly as a file and media server with occasional MySQL and http usage.
I've looked around for a similar replacement mini-server but can't find anything with the right form factor, low power usage and linux flexibility, so I was looking to see if I can optimise the throughput of my B3 as it clearly isn't a processor limitation.
Any help is welcomed.

[Gordon]

Both ethernet ports are identical. It's just for ergonomic reasons (the layout of the back panel) that eth0 is WAN and eth1 is LAN. How did you measure those speeds? May I assume that you used some service to write to and from the null device? With the firewall in place, traffic on eth0 would need to traverse more lines of code than traffic on eth, so CPU speed might still be the bottleneck. And possibly disk access if available RAM is low, which is highly probable with apache and MySQL active.

Did you test forwarding speed as well? i.e. access a third machine with the B3 as a router in between? My guess is that this will show you better numbers.

[philgaskin]

Thanks for your response Gordon.
The test wasn't as sophisticated as you may think. I plugged a laptop into the WAN port and copied a file to and from the B3 using Windows. I then did exactly the same on the LAN port - I configured a static IP on the WAN side and got a DHCP on the LAN.
I then tried copying a file from the laptop on the WAN to a PC on the LAN with the same speed as the WAN copies to and from the B3.
This led me to assume there must be something different - either hardware or software/config.
From what you are saying it may be configuration then. I am using the default IPTables firewall settings with the B3 set as Router + Firewall + Server.
I'll dig a bit deeper and see what I can find.
Thanks again.
Phil.

[Gordon]

Sounds like you may have been fooled by cache. The first time copying while attached to the WAN port the Windows machine would have to read the file from disk. The second time it would have been able to (partially) get it from memory. Similar mechanisms may have applied to the B3 and performance could also have been impacted by the physical location on the disk where the file was written to.

[SpeedingGuy]

I am running my B3 as router/NAT/NAS for my 100mbps broadband with transparent speed up till 140-150mbps (the ISP is throttling around there) BUT a year ago my original 2tb disk was starting to feel a bit sad before it totally crashed, that made a significant reduction at my through-output at the time. I was running it with the sad disk for a couple of months before it started to random crash, took it out and found that the disk was very bad. Could that be your issue?

[stasheck]

Perhaps iptables rules are different on both interfaces?