Low network performance with RTL8111/8168B using r8169 module

[Bjorn Ruud]

Ubuntu 7.10, Linux 2.6.22-14-generic #1 SMP i686 GNU/Linux

03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 01)

The r8169 module works poorly with this network controller. Samba performance was measured to ~40 Mbit/s, compared to ~240 Mbit/s on the same machine with Windows XP.

Compiling and installing the r8168 module from Realtek results in ~160 Mbit/s performance. Still not excellent, but a lot better. Sources used:
http://www.realtek.com.tw/downloads/downloadsView.aspx?Langid=1&PNid=13&PFid=5&Level=5&Conn=4&DownTypeID=3&GetDown=false#2

[Bjorn Ruud (bjorn-ruud)]

Speed measurements were obtained like this:

Mount Samba share
sudo mount.cifs //host/share /home/user/mnt -o credentials=credfile,domain=mydomain,rw,directio

Time a file copy
time cp -v src dst

Calculate transfer rate
filesize (Mbit) / transfer time (seconds)

Without the directio option in the mount command the transfers are slightly faster, but the transfer rate fluctuates a lot (it seems to oscillate).

[komputes (komputes)]

Does the slow network performance happen only with samba only or does it happen with nfs and internet downloads as well?

[Bjorn Ruud (bjorn-ruud)]

It's been a while, but if I recall correctly all network traffic was affected. Viewing the system monitor network graph showed that the traffic for a single file transfer had bursts of speed on regular intervals. It looked like it was oscillating.

Sadly I can't do more tests as I don't have a 7.10 installation to test on anymore and I currently use Intel NICs.

[Ian Weisser (ian-weisser)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 141343, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.