ATA_CAM + ZFS gives short 1-2 seconds system freeze on disk load

[Artem Belevich]

> I'd like a technical explanation of exactly what this loader.conf
> tunable does.  The sysctl -d explanation is useful if one has insight to
> what purpose it serves.  I can find mention on Solaris lists about "txg
> timeout", but the context is over my head (intended for those very
> familiar with the inner workings of ZFS).

Ben Rockwood's blog has pretty decent explanation of how transaction
groups in ZFS work:
http://www.cuddletech.com/blog/pivot/entry.php?id=1015

--Artem