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In the age of bufferbloat their buffers are too small? How many 1500-byte packets are we talking about, if it's that bad?

Unless overly large buffers are covering up the real problems with TCP?

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At 2.5 Gbps having 5 ms of buffer requires >1 MB for that single hardware queue which was either at or over the available buffer for the entire switch IIRC.

Having too large of a buffer, particularly on gigabit class software routers/nat points which use CPU+RAM instead of expensive hardware, is definitely the more common problem. There it's too easy for the trap "I have 512 MB of RAM, why shouldn't I let as much as is available be used as buffer, it's helping" which then makes you wish you had 4 MB of buffer instead.

I noted elsewhere, I fought this battle once. People outside the development team kept saying "it needs more buffers", but they were not looking at the network analyzer, and they weren't looking at the internal states. As buffers became excessive, it started with weird latency bouncing, and it just got worse and worse as you added buffers. We had a network impairment simulator. It was fun to turn that knobs on that and see how that interacted with packet loss buried in your buffer.

Why would you need 5ms of buffer?

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