WAN latency expectations?
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I've been trouble shooting some connectivity issues that have recently started to affect my ability to work from home during the covid situation. I have a Spectrum gigabit line (1000/40) and am seeing what I think is crazy high latency. I'm running with a Xeon-d 2100 based pfSense install with Intel NICs so powerful hardware.
Problems started a few months back around March with the start of covid, but this also coincided with the 2.4.5 release which had some latency issues due to some FreeBSD updates and complicated matters.
I more recently migrated to 2.5.dev builds which I think helped, but the last week or so things have been poor enough to prevent me working effectively. I had my Spectrum ISP truck roll to verify the connection quality and it tested within specs. They communicated the line was heavily utilized but there was nothing they could do to help with that other than migrate me to an enterprise account at some serious $$$$.
In terms of the latency im seeing, with zero traffic going through my WAN connection I see gateway RTT of around 15-20ms which appears fine and healthy. As soon as I start applying loads I see latency increase. With sustained traffic of circa 300mbps downloading I see latency increase to around 80ms with peaks of up to around 120ms.
With 800mbps downloads latency is up around 150-180. Is this normal, or is this indicative of a possible hardware or configuration issue or likely just line saturation during this covid scenario? -
Hi @q54e3w - at the outset it looks like some bufferbloat is developing, which may be a result of your line (cable node) being heavily utilized / congested. One thing I would recommend is trying traffic shaping with FQ-Codel to see if that will stabilize the connection:
https://forum.netgate.com/topic/112527/playing-with-fq_codel-in-2-4/815
Try setting this up and then experiment with the up and down limits until you have more stable latency under load (i.e. reduced to no bufferbloat).
Hope this helps.