[Qemu-devel] Re: [PATCH 2/3] NUMA: promoting NUMA topology to BIOS and pin guest memory

[Andre Przywara]

Avi Kivity wrote:
> Anthony Liguori wrote:
> > At this point, I'm okay with introducing the libnuma dependency for 
> > memory pinning.  I'm not sure I think we should even present this as a 
> > command line option though.  I think the command line option should 
> > just specify the NUMA topology and then we should use a monitor 
> > command for pinning (as you do on your next patch).
>
> It's helpful to have static pinning from the command line.  That's 
> useful for quick tests for those of us who don't use management interfaces.
>
> Since the monitor and command line can share code, there shouldn't be 
> any cost to this.
ACK. Actually I'd had to add code to prevent pinning from the command 
line. I think this doesn't hurt, if you use virtualization for 
partitioning (where a NUMA architecture can actually help you, because 
guests don't compete will all other guests for the memory bandwidth), it 
is quite helpful to specify everything at the beginning. Here even UP 
guest can take advantage:
-numa 1,pin:1

Regards,
Andre.

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Andre Przywara
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