Fluctuating bandwidth with 3Com 905 on gentoo

[archmonkey]

I have a problem with my NIC (3Com 905) after installing gentoo.

When transferring files either via ftp or samba, the bandwidth is fluctuating going from 0 up to at most 15 Mbit/s. Previously I was using slackware on the same machine and it worked perfectly with a fine steady bandwidth of ~70 Mbit/s

This problem is also rendering the machine useless when doing filetransfers because it takes ages just to do a simple ls in a directory.

When compiling the kernel I did choose to include the 3Com driver in the kernel and not run it as a module.

<edit>
When running a program called mii-diag it says that I have a 3c920 Series NIC adapter running... I don't know if that makes a difference
</edit>

Thanks in advance

Martin N

[mdwatts]

Originally posted by archmonkey

When compiling the kernel I did choose to include the 3Com driver in the kernel and not run it as a module.

When running a program called mii-diag it says that I have a 3c920 Series NIC adapter running... I don't know if that makes a difference


I'm not sure if compiling the driver into the kernel instead of as a module would really make a difference. Can you try as a module.

What kernel version and did you select the correct 3Com NIC support when compiling the kernel. The 2.4 kernel shows the module to likely be 3c90x.o (3c90x.ko for the 2.6).

It might be worth searching the Gentoo forums to see if others have run into the same problem with the 3Com 905.

[archmonkey]

I just tried compiling it as a module selecting the same NIC driver as the last time (3C95x)

I now have the latest gentoo kernel 2.6.7-r2, but had the same problem with the 2.6.7 kernel.

The thing that makes me think that the problem is not the NIC or the driver, but somthing else is that the whole machine is totally useless when ftp:ing. Everything is going _very_ slow. When running slackware 9.1 on a Pentium II 450 MHz I didn't have a problem at all using the machine when I was ftp:ing

But I will look in to other forums as well, thanks for the help so far.

Martin N

Machine config:
Gentoo Linux 1.4 (kernel 2.6.7-r2)
Proc: Athlon Thunderbird 1400 MHz
Mem: 256 MB DDR CAS2.5
MoBo: MSI K7T266 Pro
NIC: 3Com 3c905CX
HD: 120GB Barracuda Seagate
Gfx: ATI Rage Pro 4MB

[archmonkey]

I have, with a little help of the gentoo forum, solved my problem.

It was not a NIC problem, but a harddrive problem. I didn't have support for my VIA chipset compiled into the kernel. Adding support for VIA82CXX.. did the trick.

Because of the lack of support for VIA chipset I could not enable DMA on the harddrive and it became sloooooow.

Now it all runs smooth and fine

\Martin N

[mdwatts]

Originally posted by archmonkey

It was not a NIC problem, but a harddrive problem. I didn't have support for my VIA chipset compiled into the kernel. Adding support for VIA82CXX.. did the trick.


Ahhh the VIA chipset. I've noticed a few other threads that had hardware problems since they did not enable suppport for their chipset... especially the VIA.

Glad to see you got it all working now.