[sane-devel] Bad Performance uhci (vs. usb-ohci ,ohci)

Gene Heskett gene_heskett@iolinc.net
Sun, 10 Feb 2002 08:25:37 -0500


On Sunday 10 February 2002 06:38 am, Bertrik Sikken wrote:
>Hi,
>
>Gunther Mayer wrote:
>> the "uhci" module suffers from very bad performance
>> (linux-2.4.17).
>>
>> Scanning 150dpi A4 (merlin670 for Canon N670U over
>> libusb-0.1.4) gives: uhci:    135 sec.
>>   usb-uhci: 43 sec.
>>   ohci:     35 sec
>>
>> This corresponds to about 50K/sec for 'uhci' (and the scanner
>> must stop'n'start) !
>>
>> Is this a known bug in "uhci" ?
>
>I found something similar, with transfer rates below 100 kB/s
>while it was something like 700 kB/s before, resulting in
>heavy backtracking of the scanner head of my HP3300 scanner.
>I too used (a custom compiled) kernel 2.4.17, libusb 0.1.4 and
>uhci (compiled as module). Using the usb-uhci module instead of
>the uhci module solved it for me. I did not further research the
>issue, so I can't really tell for sure what caused the problem.
>
>Regards,
>Bertrik Sikken

How are you fellows effecting this change in usb drivers?  Here, 
on an M7VIB mobo, 1400mhz AthlonDX, I have uhci compiled in and 
have noted no such problems.  Now on my other machine, a TYAN 
TRINITY 100 mobo, any uhci eventulluy crashes if more than a 
mouse is used on the bus.

-- 
Cheers, Gene
AMD K6-III@500mhz 320M
Athlon1600XP@1400mhz  512M
98.5+% setiathome rank, not too shabby for a hillbilly