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From: Andrew Basterfield <abasterfield@gmail.com>
Subject: >4K writes to BPF
To: freebsd-net@freebsd.org
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Date: Sun, 11 Oct 2015 13:44:01 +0100
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Hi

I am playing with jumbo frames in vblade, which uses write(2) on BPF to 
put it's raw AoE packets onto ethernet.

The problem I am having is with jumbo frames; when the write is greater 
than 4K it fails with I/O error.

Is this tweakable or fundamental?

I have tried ramping up net.raw.* from 8K to 32K; no joy

thanks

Andrew Basterfield