[CentOS] slow usb hard disk performance.

Mon Dec 5 19:13:43 UTC 2005
Peter Farrow <peter at farrows.org>

Ok here is the low down:

Machine 1:
PII 450 Compaq, with an Intel USB controller, this is the same dog 
machine I just replaced in the previous thread
Kernel: 2.6.9-22.0.1.EL
512 Megs RAM
Don't know what the usb controller was but its Intel, and its USB 1
Speed: 1000K/sec consistent

Machine 2:
Intel 440GX+ in an SC5000 chassis 2 x PIII 1GHz CPU
00:12.2 USB Controller: Intel Corporation 82371AB/EB/MB PIIX4 USB (rev 01)
1024 Megs RAM
Kernel: 2.6.9-22.0.1.ELsmp
Speed: 1000K/sec consistent

Machine 3:
VIA C3 600MHz EPIA
Kernel : 2.6.9-22.0.1.EL
00:10.0 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 
Controller (rev 80)
00:10.1 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 
Controller (rev 80)
00:10.2 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 
Controller (rev 80)
00:10.3 USB Controller: VIA Technologies, Inc. USB 2.0 (rev 82)
512Megs RAM
Speed: 4.95M/sec consistent from a remote putty shell (via SSH)
Erratic when hdparm run from the text console....

I know these machines aren't bleeding edge but the VIA C3 box is the 
intended target, its silent and fanless and smaller than the yellow 
pages book by a fair margin.  It also has two nics onboard making it 
ideal for a home firewall (its current use).

USB ports are arranged in two pairs, and I tried one socket in each, 
from the LSPCI looks like only one of these is USB2 - cooments invited

/proc/CPUinfo shows the cpu at 400MHz not sure if this is accurate I 
will check the BIOS as its supposed to be 600MHz.

If you're telling me 4.95Megs/sec is about tops then I might be able to 
by that...

Ideas welcome....

Pete












If you reckon


Bryan J. Smith wrote:

>Les Mikesell <lesmikesell at gmail.com> wrote:
>  
>
>>What Linux kernel versions have you used with firewire? 
>>    
>>
>
>Late 2.4.2x, as well as 2.6.x -- basically RHL9/FC1/RHEL3 and
>FC3/RHEL4.  I do have to rebuild for FireWire support in
>RHEL4, yes.
>
>  
>
>>The last 2 fedora FC4 updates broke disk access completely.
>>    
>>
>
>
>I ain't touching FC4.  ;->
>
>  
>
>>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.
>>    
>>
>
>Repeat after me ...  ;->
>"USB and FireWire should _not_ be used as 24x7 on-line
>storage"
>
>Despite Apple's prior claims, it has become more apparent
>than ever that FireWire is _not_ a 24x7 on-line storage
>solution.  Do not use it as such, use it as a temporary,
>near-line storage solution that you plug-in and use just when
>you need it.  I've learned that hard lesson even on Apple's
>own XServe platforms.
>
>  
>
>>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.
>>    
>>
>
>I've had no problem with my disks, Digital8 and DV cams,
>etc...  They all work great!  But I don't leave the disks or
>camera connected for a day at a time, I plug-in, use and then
>I unplug when finished.
>
>Regardless of OS -- Linux, MacOS X or Windows -- FireWire and
>USB are nothing but trouble when it comes to leaving them
>connected.  They are a "temporary plug and unplug" solution
>AFAIAC.
>
>If you want reliable, external storage, consider SCSI or ...
>better yet ... Serial Attached SCSI (SAS).
>
>
>  
>