[geeks] Intel Mac Mini - Horrible USB2 drive performance

[John Francini]

Well, the people who automatically trot out "use firewire, it's a 
better interface" are correct. It's designed from the start to be a 
high-speed mass-storage interface, rather than having mass-storage 
features 'bolted-on' to what is, in essence, a replacement for 
various slow serial buses.

Be that as it may, the real problem appears to be a disagreement 
between the USB2 chipset in your enclosure and your Mac mini.  There 
are a number of different USB chipsets out there -- some get on 
better than others with Macs.

If you use Apple System Profiler, it should tell you the specifics 
about whether the Mac thinks it's talking to a USB 2.0-capable device 
or merely a USB 1.1-capable one.  If it's the latter, you're 
deliberately being throttled back to approx. 1 MB/s throughput.

If you insist on staying with USB, I'd suggest replacing the 
enclosures with ones from companies who sell a lot into the Mac 
market -- Other World Computing comes to mind.  (They're at 
<http://eshop.macsales.com/>.  Highly recommended.)

John Francini



At 10:51 -0400 5/24/07, 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.
>
>
>
>Help?!?
>
>
>
>-Anthony
>_______________________________________________
>GEEKS:  http://www.sunhelp.org/mailman/listinfo/geeks

-- 
John Francini, francini at mac.com

"The journey is more important than the destination -- that's part of life.
If you only live for getting to the end, you're almost always disappointed."
                               -- Donald Knuth