Is SQM still recommended if my BufferBloat is already at A

I'm reading some best practices guides for OpenWRT and one of them is to enable SQM which helps with BufferBloat. But what if my BufferBloat is already at A rating? Is it still needed? Screenshot for my speedtest:

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If you’re happy with your line under load, then SQM will only slow it down. If you need traffic prioritization under load (VOIP, for example), give it a try.


As @jeff writes, if you are happy with your line as is, no need to change anything. SQM has a few tricks up its sleeve that can help once you experience heavy network loads (like "isolation" of your internal hosys from each other, and prioritization of new and/or sparse flows), but if you operate your access link like a backbone (try to keep load well below 100% of capacity at all times) SQM is not going to help (much) for latency (it will give you a somewhat better mixing of concurrent flows which should keep jitter per flow somewhat better in check than the typically unmanaged single queue in the NIC driver). In short it is a policy decision you need to make for your network.

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There is a saying that is often forgotten or ignored in the tech world. "If it's not broken, don't fix it."

Depends more on how much bufferbloat there really is.
Got an "A" on dslreports but still had about 50ms or more of bufferbloat.
With SQM I was able to reduce it to 1-2ms. :+1:

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