> + Linear mode: the input precision is defined as 100-(MBA_MAX). > For instance, > + if the MBA_MAX value is 90, the input precision is 10%. Values > not an even > + multiple of the precision (e.g., 12%) will be rounded down > (e.g., to 10% > + delay applied) by HW automatically.
No sure if all people unterstand HW, if not then I prefer Hardware. If you do this then all places though the document should be replaced. > + When context switch happens, the COS ID of VCPU is written to per- > thread MSR COS ID is per-domain other than per-vCPU at this time. So 'COS ID of domain' is more accurate. > + `IA32_PQR_ASSOC`, and then hardware enforces bandwidth allocation > according > + to the throttling value stored in the COS register. There is no COS register in fact. COS exists just a concept. > +For example: > + root@:~$ xl psr-hwinfo --mba > + Memory Bandwidth Allocation (MBA): > + Socket ID : 0 > + Linear Mode : Enabled > + Maximum COS : 7 > + Maximum Throttling Value: 90 > + Default Throttling Value: 0 > + > + root@:~$ xl psr-mba-set 1 0xa > + > + root@:~$ xl psr-mba-show 1 > + Socket ID : 0 > + Default THRTL : 0 > + ID NAME THRTL > + 1 ubuntu14 0xa > + > +# Areas for improvement > + > +A hexadecimal number is used to show THRTL for a domain now. It may > not be user- > +friendly. > + > +To improve this, the libxl interfaces can be wrapped in libvirt to > provide more > +usr-friendly interfaces to user, e.g. a percentage number to show for > linear > +mode. I suggest we can do this even for 'xl psr-mba-show', as we know we are in linear mode or not. A hex number is just not easy to understand for people. And for 'xl psr-mba-set' it is also much straighforward to set a percentage number in linear mode. Chao _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
