Hi, that looks good. Processors 0 and 4 are not used in pinning and remain on the host OS. https://en.wikipedia.org/wiki/Hyper-threading Basically as soon as you load one OS CPU on a physical core the other HT core will be able to perform a lot less stuff.
This should provide the guest some details of the provided vCPUs: <topology sockets='1' cores='3' threads='2'/> 2015-12-28 6:55 GMT+01:00 thibaut noah <[email protected]>: > So is this the right emulation? If i understand correctly what i'm trying to > get is a 3cores with 2threads per core ? (so 6cores pinned?) > I don't have that much knowledge in cpu so i'm kinda lost here. > > <cputune> > <vcpupin vcpu='0' cpuset='1'/> > <vcpupin vcpu='1' cpuset='2'/> > <vcpupin vcpu='2' cpuset='3'/> > <vcpupin vcpu='3' cpuset='5'/> > <vcpupin vcpu='4' cpuset='6'/> > <vcpupin vcpu='5' cpuset='7'/> > </cputune> > > 2015-12-26 18:53 GMT+01:00 Karsten Elfenbein <[email protected]>: >> >> check that the 2 cores for the host OS are on the same physical core >> and that the VM does not use those 2 processors with the same core id >> >> cat /proc/cpuinfo | grep -e processor -e 'core id' >> >> CPU 0-3 should be the core 0-3 >> CPU 4-7 should be the core 0-3 again with HT >> >> so leaving out CPU 0 and 4 should keep core 0 idle and the host OS >> responsive >> >> taskset 1-3,5-7 startVM.sh >> >> Karsten >> >> 2015-12-26 12:56 GMT+01:00 Eddie Yen <[email protected]>: >> > Pining CPU can reduce the happening that host and guest using the same >> > thread at the same time. >> > >> > And I don't know which program you're using on Fedora, so I don't have >> > quite >> > answer that 2 threads is enough for host or not. >> > It's all depends on your usage case. >> > >> > 2015-12-26 19:44 GMT+08:00 thibaut noah <[email protected]>: >> >> >> >> My cpu is a i7 4790k, is pinning the cpu usefull ? I'll try to derp a >> >> bit >> >> with the vcpu thing, just afraid 2 threads aren't enough for fedora :/ >> >> >> >> 2015-12-26 11:59 GMT+01:00 Eddie Yen <[email protected]>: >> >>> >> >>> I forgot your CPU type, so I don't know about your case. >> >>> >> >>> But, as I'm using 4820K, I usually using 4 to 6 threads gave to VM, >> >>> only >> >>> use 2 threads for Fedora host. >> >>> And most important is vCPU tweaks, especially CPU topology and >> >>> Hyper-V. >> >>> >> >>> For me, I usually set topology as "sockets=1 cores=6 threads=1" if >> >>> using >> >>> 6 threads from host. >> >>> Then set cpuset= to let vCPU worked on pointed CPU threads. >> >>> >> >>> IME, set all threads as vCPU cores can got better performance on >> >>> Windows >> >>> 10. >> >>> >> >>> 2015-12-26 18:00 GMT+08:00 thibaut noah <[email protected]>: >> >>>> >> >>>> Hello guys merry christmas ! o/ >> >>>> My current issue is vm and host optimization, i use my windows 10 vm >> >>>> for >> >>>> gaming purposes only (like most of us i think), problem is, to keep >> >>>> my >> >>>> performances on windows high i drain too much ressources on my fedora >> >>>> host >> >>>> thus making it almost useless (also when leaving the vm i most of the >> >>>> time >> >>>> found myself unable to use fedora at all so i have to reboot...). >> >>>> So is it possible to improve performances to the max on the guest >> >>>> without almost killing the host ? >> >>>> Should i consider switching my gear for a bi-xeon? (to assign one >> >>>> fully >> >>>> to the host and one to the guest) >> >>>> I'm actually not sure about what happen here, does anyone ran into >> >>>> the >> >>>> same sort of issue? >> >>>> Have a good day >> >>>> >> >>>> _______________________________________________ >> >>>> vfio-users mailing list >> >>>> [email protected] >> >>>> https://www.redhat.com/mailman/listinfo/vfio-users >> >>>> >> >>> >> >> >> > >> > >> > _______________________________________________ >> > vfio-users mailing list >> > [email protected] >> > https://www.redhat.com/mailman/listinfo/vfio-users >> > > > _______________________________________________ vfio-users mailing list [email protected] https://www.redhat.com/mailman/listinfo/vfio-users
