[Xen-devel] Xen & I/O in clusters - problems!

[Rune Johan Andresen <runejoha@xxxxxxxxxxx>]

Hi, we are benchmarking Xen in a cluster, and got some bad results. We might do something wrong, and wonder if anyone
have similar problems. 

When we benchmark troughput from native Linux to native Linux (two physical nodes in the cluster) we get 786.034 MByte/s
When we benchmark from a virtual domain  (running on Xen on a physical node) to an another virtual domain (on another physical node) we get
56.480 MByte/s (1:16) 

The difference is huge, and we wonder if the bottleneck could be the fact that we are using software routing (We use this in order to route from the physical node to the virtual OSs), or if this is just a downside of Xen? 

I would guess it IS the SW routing, so is there any good alternatives to make virtual domains communicate on a cluster without sw routing? 

cheers,
Rune J.A