Re: [PATCH] vhost: Add polling mode

[Razya Ladelsky]

> > 
> > Hi Michael,
> > 
> > Sorry for the delay, had some problems with my mailbox, and I realized 

> > just now that 
> > my reply wasn't sent.
> > The vm indeed ALWAYS utilized 100% cpu, whether polling was enabled or 

> > not.
> > The vhost thread utilized less than 100% (of the other cpu) when 
polling 
> > was disabled.
> > Enabling polling increased its utilization to 100% (in which case both 

> > cpus were 100% utilized). 
> 
> Hmm this means the testing wasn't successful then, as you said:
> 
>    The idea was to get it 100% loaded, so we can see that the polling is
>    getting it to produce higher throughput.
> 
> in fact here you are producing more throughput but spending more power
> to produce it, which can have any number of explanations besides polling
> improving the efficiency. For example, increasing system load might
> disable host power management.
>

Hi Michael,
I re-ran the tests, this time with the  "turbo mode" and  "C-states" 
features off.
No Polling:
1 VM running netperf (msg size 64B): 1107 Mbits/sec
 Polling:
1 VM running netperf (msg size 64B): 1572 Mbits/sec








As you can see from the new results, the numbers are lower, 
but relatively (polling on/off) there's no change.
Thank you,
Razya


 


 
> 
> > > -- 
> > > MST
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