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Re: Domain-0 CPU pinning - is it still a best practice?

> for xl). Are people still dedicating CPU cores to dom0 in modern
> versions of Xen with credit2 scheduler?
> If I put this on the hypervisor command line:
>    dom0_max_vcpus=2 dom0_vcpus_pin
> how do I know which PCPUs dom0 will be pinned to?

I do this, but then I take it a little bit further, especially with NUMA hosts.

Let’s suppose I have a dual-socket 8-core CPU machine with HT enabled. 32 
logical CPUs, right?

I use those hypervisor command line configs and some commands in rc.local to 
end up with the following:

# xl cpupool-list
Name               CPUs   Sched     Active   Domain count
Pool-dom0            4    credit       y          1
Pool-CPU1           12    credit       y          5
Pool-CPU2           16    credit       y          3

dom0 ends up being assigned the first 2 physical cores on the first CPU (4 

I then have cpu pools for the remainder of the first cpu and then the whole 
entire second CPU.

This gives me plenty of dedicated horsepower for handling IO and s/w RAID ops.

xl cpupool-numa-split
xl cpupool-rename Pool-0 Pool-dom0;

xl cpupool-cpu-remove Pool-dom0 4
xl cpupool-cpu-remove Pool-dom0 5

xl cpupool-create name=\"Pool-CPU1\" 
xl cpupool-create name=\"Pool-CPU2\" 




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