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Subject: Re: 8.0-RELEASE/amd64 - full ZFS install - low read and write disk
 performance
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On 01/25/10 19:53, Jeremy Chadwick wrote:

> That's just the thing -- I/O transactions, not to mention ZFS itself,
> are CPU-bound.  If you start seeing slow I/O as a result of the Atom's
> limitations, I don't think there's anything that can be done about it.
> Choose wisely.  :-)

It's not *that* terrible. They still do DMA and have more than decent 
(ICH) controllers so CPU is not really saturated. On my netbook with the 
1st gen Atom and ICH7, reading the drive at full speed (cca 60 MB/s) 
barely even registers in sys and intr time.

Unless ZFS compression is used, Atoms are enough for file servers [*] :)


[*] Unless they are, like mine, paired with a Realtek NIC, which is the 
*real* performance bottleneck.