DNS performance on Windows

Just to remember: I've got experience with heavy loaded domain controller with queries rate above 40k per second (yes, 40 thousand per second). The main problem on this virtual domain controller it was high cpu0 utilization and low load on other cpu. As I can remember - it was VMWare vm with 16 cores (virtual cores on operating system). What should be done in this case to improve performance? Upgrade of virtual hardware and network subsystem.

dnscmd - records from command line

DNSCMD dns1.my.internal.domain /RecordAdd my.internal.domain newhost CNAME orighost.my.internal.domain.

DNSCMD dns1.my.internal.domain /RecordAdd my.internal.domain newhost.my.internal.domain. CNAME orighost.my.internal.domain.

DNSCMD dns1.my.internal.domain /RecordAdd my.internal.domain A 10.1.1.17

Of course small/capital letters are not important - only for better understanding. Why to use DNSCMD still? Because not everywhere I can use PowerShell to register record and in this way it is much simpler than using GUI console of course.