[ovirt-users] Re: High performance VM cannot migrate due to TSC frequency

On Fri, Dec 11, 2020 at 5:39 PM Milan Zamazal <mzamazal(a)redhat.com&gt; wrote: See here: [root@ov200 ~]# virsh -r capabilities | grep "name='tsc'" <counter name='tsc' frequency='3457996000' scaling='no'/> [root@ov200 ~]# [root@ov300 ~]# virsh -r capabilities | grep "name='tsc'" <counter name='tsc' frequency='3457988000' scaling='no'/> [root@ov300 ~]# [root@ov301 ~]# virsh -r capabilities | grep "name='tsc'" <counter name='tsc' frequency='3457997000' scaling='no'/> [root@ov301 ~]# The three hosts have the same model cpu Model name: Intel(R) Xeon(R) CPU X5690 @ 3.47GHz and slightly different actual frequencies at a certain moment... But what does it mean so the checkbox Migrate only to hosts with the same TSC frequency if even if I don't check it the migration is prevented? BTW the command lscpu produces exactly the same output on the three hosts, apart "CPU MHz" and corresponding "BogoMIPS" that slightly change each time I run the command. And the flags for all are: Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 popcnt aes lahf_lm pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid dtherm ida arat flush_l1d Gianluca