[CentOS] slow usb hard disk performance.

Mon Dec 5 18:01:48 UTC 2005
Les Mikesell <lesmikesell at gmail.com>

On Mon, 2005-12-05 at 10:01, Bryan J. Smith wrote:

> I'd normally suggest you ensure you're connecting to an EHCI
> port with USBView (or Device Manager in Windows XP), but
> you've already stated that you had good performance in
> Windows XP.
> 
> The only other thing I can suggest, which really isn't an
> answer, is to use FireWire.  I've never had any performance
> issues, period.  And there's no worrying whether or not you
> are connected to an OHCI or EHCI port, how well the driver
> handles memory mapped I/O for the target side, etc...
> 
> FireWire was designed for block transfer devices, with
> intelligence allowing direct device-to-device transfers.  USB
> was designed for character devices and programmed I/O, EHCI
> wasn't supposed to exist (but exists more out of Intel's
> refusal to license IEEE1394 -- long, long story -- which has
> affected adoption as well).

What Linux kernel versions have you used with firewire?  The
last 2 fedora FC4 updates broke disk access completely.  FC3
sort-of works, but when I leave a RAID1 mirror running with
an IDE partition and a firewire partition mirrored, within
a few hours of activity either the machine will crash or
the firewire partition will be kicked out of the RAID.
I haven't tried Centos because you need the unsupported
kernel and I didn't have much hope for that being better
than any of the fedoras.

-- 
  Les Mikesell
   lesmikesell at gmail.com