[fedora-arm] Slow USB storage on A9 processors

[Jeffrey Bastian]

On 2011-09-13 10:18, Mark Salter wrote:
> These numbers are for SD card in an mmc slot, right? I wouldn't expect
> the patch to the USB EHCI driver to have any effect on SD card speed.

Oh, you're right.  I ran bonnie++ against a USB hard drive and it shows 
a whopping improvement!

I've edited my blog post and added the USB hard drive numbers:
http://jeffbastian.blogspot.com/2011/09/storage-speed-on-pandaboard-revisited.html


> The big write performance hits are worrisome, though. I'd be good to
> test on one kernel version with and without the patch just to make sure.
> Also comparing SD performance with and without nosmp passed on cmdline
> would be interesting.


Okay, so I should run 8 tests?
   patch       smp      sd-card
   patch       smp      usb-hd
   patch       nosmp    sd-card
   patch       nosmp    usb-hd
   no-patch    smp      sd-card
   no-patch    smp      usb-hd
   no-patch    nosmp    sd-card
   no-patch    nosmp    usb-hd

Jeff