[openib-general] Re: Re: [PATCH] IPoIB splitting CQ, increase both send/recv poll NUM_WC & interval

[Michael S. Tsirkin]

Quoting r. Shirley Ma <xma at us.ibm.com>:
> Subject: Re: [openib-general] Re: Re: [PATCH] IPoIB splitting CQ,?increase both send/recv poll NUM_WC & interval
> 
> 
> Michael,
> 
> smp kernel on UP result is very bad. It dropped 40% throughput.
> up kernel on UP thoughput dropped with cpu utilization dropped from 75% idle to 52% idle.

Hmm. So far it seems the approach only works well on 2 CPUs.

> I didn't see latency difference. I used TCP_RR test.

This is somewhat surprising, isn't it? One would explain the extra
context switch to have some effect on latency, would one not?

-- 
MST