Netgate C2758 - PPPoE Performance (pfSense +)

Phobia

Hello all,

I'm looking for some help to figure out if I'm running up against a CPU limitation, or if further optimization may be possible.

I'm subscribed to a FTTH service that provides a 1.5Gbit/s connection, and am using a GPON ONT module connected directly into a Broadcom BXE 10g card, running a patched driver to allow for the ONT to sync at 2.5Gbit/s.

(https://www.dslreports.com/forum/r32230041-Internet-Bypassing-the-HH3K-up-to-2-5Gbps-using-a-BCM57810S-NIC)

Various speed tests seem show a limit being hit just over 1050Mbit/s. Observations via HTOP show that one of the cores on the C2758 is hitting 100% utilization during the download portion of the test.

I've tried a variety of tuning settings, but before continuing to tweak, I thought I should ask if the C2758 CPU should be expected to achieve much a much better result.

I've read that in freeBSD, the PPPoE implementation may be limited to a single thread for RX, but had hoped that the latest pfSense version might overcome that. I had been running the last 2.4.5-p1 release, but have updated and am seeing similar results.

Current info:
pfSense Version 21.02-RELEASE-p1 (amd64)
acme and rrd summary packages installed

So all of that to say - is the C2758 going to be constrained with a PPPoE based Internet connection to about 1G speeds?

If yes - what hardware would be recommended in its place?

Thanks in advance for your thoughts.

stephenw10

It's unlikely you would see 1.5Gbps because of the know limitations PPPoE introduces.

If you have applied the settings shown here there isn't much more you can do:
https://docs.netgate.com/pfsense/en/latest/hardware/tune.html#pppoe-with-multi-queue-nics

You need something with high single thread performance to reach that.

Steve

Phobia

@stephenw10 thanks for that. Any recommendations on hardware or single core passmark scores required for 1.5Gbit? The C2758 seems to score 333 for single core, but Passmark also says the error probability is high as there were only 4 samples taken with that processor.

I'm not clear if the increase in performance is linear, or if there are other caveats.

Any advice?

stephenw10

Not really unfortunately. I did test the C3558 at 1Gbps for PPPoE locally but I couldn't tell you what that might scale to.

Steve

Phobia

@stephenw10 OK - thanks. I think I'll look at moving away from the Atom based platform then. Maybe a different Supermicro motherboard based on the Xeon D-1518 which has a single core passmark score of about 1200.

Double the power consumption of the Atom, unfortunately.

stephenw10

Double the TDP maybe but that does not represent consumption given the same load.

You might consider something with less cores at higher frequency instead.

Steve