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<DIV><FONT size=2>Dear all develpers:</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2> I have a USB modem, it can reach the
download speed up to 7.2Mbps and the upload speed up to 5.76Mpbs.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2> On the Ubuntu 8.10, kernel version 2.6.27, the
system will load the USB serial driver /lib/.../drivers/usb/serial/option.ko for
my USB modem device.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2> And after dialing up with baud rate 115200, I can
get the download speed to be 7.2Mpbs, but however, I can only get the upload
speed to be 1.5Mpbs. </FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2> I modified the option.c code, and changed the out
queue length and size as follows:<BR>
<BR> /* per port private data */<BR> #define
N_IN_URB 4<BR> -#define N_OUT_URB
1<BR> +#define N_OUT_URB 4<BR> #define
IN_BUFLEN 4096<BR> -#define OUT_BUFLEN
128<BR> +#define OUT_BUFLEN 4096</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2> Then reload the new option.ko driver for my
USB modem, but however, the upload speed is still keeping
1.5Mpbs.<BR> I don't know why, and I also don't know where the
upload speed is limited.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2> Can who can tell me why it is? Is it the
problems of the kernel driver? Or is it the problems of the system
settings?<BR> Wait for the help urgently!</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Best Regards,</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>Franko Fang</FONT></DIV>
<DIV><FONT size=2>2008-12-31</FONT></DIV></BODY></HTML>