Disable Hyperthreading online

Question

I have an Ubuntu server which has the following attributes ( snapshot)

processor : 23 vendor_id : GenuineIntel cpu family : 6 model : 44 model name : Intel(R) Xeon(R) CPU X5690 @ 3.47GHz stepping : 2 cpu MHz : 1600.000 cache size : 12288 KB physical id : 1 siblings : 12 core id : 10 cpu cores : 6

For the system under test, hyper threading is enabled. I want to disable the hyper threading for this system. I don't want to boot up and go to BIOS to do so but want to get it done online. Several suggestions I came across were to do something like below:

'echo 0 >/sys/devices/system/node/node0/cpu2/online'

I am not sure which CPU or node shall I go to and perform the following operation based on the numbers of CPU cores, siblings in the system.

Any idea?

Answer 1

I am not sure which CPU or node shall I go to and perform the following operation 
based on the numbers of CPU cores, siblings in the system.

Parallel benchmarking the system would assess performance and maximum throughput of a multi core CPU's, which can tell us enabling/disabling of hyper threading for the system.