Hi folks,
I have a few questions/clarifications about dom0 network I/O scalability. I would appreciate any feedback/pointers.
So the current implementation of netback does not scale beyond a single CPU core, thanks to the use of tasklets, making it a bottleneck (please correct me if I am wrong). I remember coming across some patches which attempts to use softirqs instead of tasklets to solve this issue. But the latest version of linux-2.6-xen.hg repo does not include them. Are they included in some other version of dom0 Linux? Or will they be included in future? This seems like a very important problem to solve especially as the number of VMs and number of CPU cores go up. Is there any fundamental limitation in solving this problem?
Thanks. --Kaushik |