Thinkpads Forum

Hi,

I have two USB memory sticks, one is USB 1.1, the other 2.0.
On Windows XP, the 2.0 stick is a lot faster than the 1.1. On OS/2, the same sticks seem to be about equally fast (slow).

The basedev entries in config.sys:
BASEDEV=USBUHCD.SYS
BASEDEV=USBUHCD.SYS
BASEDEV=USBUHCD.SYS
BASEDEV=USBEHCD.SYS
BASEDEV=USBD.SYS
rem /REQ:USBUHCD$,USBOHCD$,USBEHCD$
BASEDEV=USBHID.SYS
BASEDEV=USBMSD.ADD /FLOPPIES:0

buildlevel is 10.145

The three uhcd and the one ehcd show up in the hardware manager folder, so they all are loaded. They all seem to use interrupt 11. Int 11 also seems to be used by the IBMPRISM driver.

I already tried to free up interrupts (by disabling stuff from within the BIOS), so the sharing wouldn't occur. However, the interrupt is still being shared... Is this the right path I should follow to speed up USB 2.0?

Any ideas?

Best regards,
Jeroen Besse

http://www.os2world.com
There is a forum at the above site that has a similar discussion. It might be about what you are asking for.

Have you tried the newer usb drivers from http://www.ecomstation.com ?

There are working on usb drivers at http://www.netlabs.org .

The drivers that I use are the latest.

Further investigation shows:

- Copying a 16 MB file from a USB 2.0 stick to harddisk takes about 4 seconds;
- Copying a 16 MB file from harddisk to a USB 2.0 stick takes almost 2 minutes.

On exactly the same hardware, but with WinXP (it's dual-boot), from stick to harddisk takes about 5 seconds, from harddisk to stick somewhere between 20-30 seconds.

I tried an USB 1.1 stick, the same file goes to and from in some 20-30 seconds. So copying to a stick is faster with USB 1.1 than with USB 2.0!

It seems you have a poor quality USB2 stick!

3-5 MB/sec read speed over USB2 is pretty normal for any flash media, that's what you get in both OS/2 and XP.
Write speed of your stick is already below-standard in XP, and it seems that the stick's hardware is "optimized" for the transfer block size usually chosen by the XP USB driver. OS/2 might use differently sized (bigger/smaller) chunks of data to transfer, and then performance gets extremely bad. Why that? The manufacturer simply saved a few cents of cost by omitting a few kB RAM buffer inside the stick.

Robert_L wrote:It seems you have a poor quality USB2 stick!

Gee... I thought Kingston was quite good...