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Should I expect random (or even regularly-occurring) bit errors to cause corrupted/dropped PDUs (packets) proportionate to the PDU size ?

Troubleshooting high (0.01% to 0.1%) packet loss over a short (<1ms) 2-hop path, 1Gbps+.

I ran these two pings concurrently.
Pretty sure their combined traffic volume shouldn't be enough to cause (too much) contention between the two.
Would probably do well to gather a larger sample size / longer run, but here we are for now.

ping -c 1200001 -s    4 -W 2 -qni 0.001 10.0.0.1
    --- 10.0.0.1 ping statistics ---
    1200001 packets transmitted, 1199002 received, 0.0832499% packet loss, time 1222942ms

ping -c 1200002 -s 1192 -W 2 -qni 0.001 10.0.0.1
    --- 10.0.0.1 ping statistics ---
    1200002 packets transmitted, 1199224 received, 0.0648332% packet loss, time 1235676ms

Wouldn't we expect (over a long enough sampling period) for the 1220 byte packets to be dropped proportionately more often than the 32 byte packets ?

Yet above, the 32 byte packets see higher loss ...
Can we reasonably infer, then, that the cause of the loss is likely not bit-error-related ?

Bonus : Someone advised me that ...

32 byte packets are far more lossy then 1220, because of all the excessive headers, and CRCs and so forth.

Is this true ?
What is the mechanism behind smaller packets being inherently more lossy ?

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Should I expect random (or even regularly-occurring) bit errors to cause corrupted/dropped PDUs (packets) proportionate to the PDU size ?

Yes - for truly random errors. However, most often transmission errors are not entirely random but more likely with specific patterns (especially on copper) which are not trivial.

pinging doesn't provide really useful probing as ICMP packets can be dropped for a variety of reasons, not just checksum errors (esp. ICMP rate limiting, processing contention, QoS).

If you really want to troubleshoot packet loss on a multi-hop path, check the error counters on all intermediate devices' interfaces while you fire some high-bandwidth streams across the links in each direction and both simultaneously. Anything flaky should show up.

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