[Beowulf] Realtek 8169 performance problem

[Daniel Dotta]

Hi All:

         We have been installing a linux cluster (Mandrake 10 with diskless
clients) with motherboard and processor (3.0 GHz) Intel and network
interfaces Realtek 8169 Fast/Gigabit Ethernet. We actualized  the kernel to
2.6.11 to update de network interface driver.

          We are having performance problems (we are using a our mpich
application to test the performance) when we connect the system in Gigabit
Ethernet. The performance is worse than Fast Ethernet connection (we change
the switch to verify this). The performance would be better when we use
gigabit ethernet.  We thought that can be a switch problem so we use a cross
cable to connect directly two PCs and the low performance keep.

So I would like to know if anyone had a similar performance problem with
this network interface? Would be a diferent configuration for the network
interface or when I operate in Gigabit mode? Someone could suggest a good
gigabit network interface for we test and compare the performance?

Thanks in advance,

Daniel Dotta