[ It looks like I didn't send this earlier ]

> Are you, by any chance, setting the tunable 'hw.ata.ata_dma' to 0 to
> disable DMA?
> I ask this because in the dmesg above you have:
> ada0: 300.000MB/s transfers (SATA 2.x, PIO4, PIO 8192bytes)
> In my setup, I get this instead:
> ada0: 300.000MB/s transfers (SATA 2.x, UDMA6, PIO 8192bytes)

Hi Neel,

Good eyes, indeed I do! Very nice.

# grep -rh ata_dma .
    echo 'hw.ata.ata_dma="0"'  >> boot/device.hints

My VCS log says I added it 6 years ago -- "disable DMA for better Soekris/Alix 
support”, which probably seemed like a very specific commit message at the 
time. For what it's worth the system is booting fine without the setting on my 
alix and soekris boards, too.

Thank you!

The ZFS devmode didn't seem to make a difference for this; but setting it to 
'dev' did fix some warnings I was getting when making snapshots, so that was 
useful too. Thank you, Allan.

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