Re: [PATCH] Network Checksum Removal

[Bin Ren <bin.ren@gmail.com>]

On 5/24/05, Ian Pratt <m+Ian.Pratt@cl.cam.ac.uk> wrote:
> > What currently I'm really really obssessed is (1)
> > dom1->external with default BVT gives only ~400Mbps (2)
> > dom1->external with my EEVDF scheduler (everything else is
> > exactly the same) gives 610Mbps, very close to
> > dom0->external. With scheduler latency histograms, it seems
> > to be caused by *far too frequent* context switches in BVT.
> > I'm still digging.
> 
> Have you tried SEDF? I'm itching to make it the default scheduler...
> 
> Ian

The following numbers are all for dom1->external. Each test runs 50
seconds. dom0/1 shares one CPU.

With default SEDF, throughput is even worse than default BVT: 318Mbps
(down from 410Mbps). I guess, without looking into the source codes,
default SEDF, dom0 and dom1 both get 50% of CPU. I tweaked their CPU
shares and get the followings:

dom1 60%: 493Mbps
dom1 70%: 371Mbps
dom1 80%: 243Mbps

After these tests, dom0 /proc/interrupts is:

           CPU0
 14:      11148        Phys-irq  ide0
 15:          2        Phys-irq  ide1
 16:    1722970        Phys-irq  eth0
 21:          0        Phys-irq  uhci_hcd, uhci_hcd, uhci_hcd, uhci_hcd
256:          5     Dynamic-irq  ctrl-if
257:      92682     Dynamic-irq  timer0
258:         35     Dynamic-irq  console
259:          0     Dynamic-irq  net-be-dbg
260:       4842     Dynamic-irq  blkif-backend
261:    2943112     Dynamic-irq  vif1.0
NMI:          0
LOC:          0
ERR:          0
MIS:          0

dom1 /proc/interrupts is:

           CPU0
256:        474     Dynamic-irq  ctrl-if
257:      45584     Dynamic-irq  timer0
258:       5158     Dynamic-irq  blkif
259:    1097273     Dynamic-irq  eth0
NMI:          0
ERR:          0

SEDF doesn't work out of box and parameter tuning is tricky as for
driver domains.

- Bin