[geeks] Intel Mac Mini - Horrible USB2 drive performance

[Sridhar Ayengar]

geeks at litfire.com wrote:
> Not sure if anyone can help with this or maybe commiserate if there's
> nothing to be done.
> 
> I have an Intel Core Duo Mac Mini I've been trying to use as my iTunes
> library device to feed my AppleTV.  I'm happy with the plan, using Handbrake
> to deal with DVD to aTV, etc.
> 
> What I'm not happy about is the performance of external USB2 drives on the
> Mini.  XBench for the two drives I got (500GB, one a Cavalry, the other a WD
> MyBook Essential) show sub-1MB/sec throughput - which corresponds rather
> well, unfortunately, with the real-world performance I'm seeing with a few
> dozen gigs taking the better part of a calendar day to copy.
> 
> Aside from the "Use FireWire, it's a better interface" which I know that
> many tend to whip out around Macs, I think that performance that crappy is
> indicative of a problem.  Unplugging from the Mac and plugging into my XP
> box shows the limitations of the interface - at 33MB/s or so.  Same two
> drives, and I reformatted NTFS or HFS+ based upon which machine I was
> checking.
> 
> Horribly enough, mounting the same drives as an SMB share over GigE
> benchmarks over 30MB/sec on the Mini!
> 
> Has anyone got any insight into how to undo whatever idiotic thing is
> causing the problem?  I don't think that "buy firewire enclosures and move
> the drives" is a legitimate answer.  I've been told in an IRC channel that I
> frequent that the MacOS X USB drivers are to blame, but I can't find any
> reliable back-up for that notion.

Are you certain that the device is connecting to the Mac in USB 2.0 
mode?  It might only be connecting in USB 1.1 mode, which would lead to 
the symptoms you describe.

Peace...  Sridhar