Disabling Hyper Threading on many core CPU ?

Latest response

Newer Intel's CPU like E5-46xx/26xx/24xx/16xx V2 have many cores per socket. Let's say you got one with 10 cores per CPU, in typical server with 2 CPU that is 20 cores. Is there any real world case where you would need Hyper Threading on top of that?

Any thoughts about this ?

Responses

Hyper Threading is not just about increasing the number of cores, it's to improve the efficiency of the physical cores. Intel systems running with 64 physical cores (8x8) aren't uncommon (at time of writing), and HT is still recommended for these systems.

Unless the vendor for the software you plan to use explicitly requests that it be turned off, or you have benchmarked the workload with HT off and shown improvement, I would be leaving it on.

Interested to know if anyone else has had specific (recent) experiences that have caused them to turn it off?

-edit-

Found the following support references which essentially suggest the same as above. Haven't been able to find a Red Hat white paper with general recommendations.

JBoss on RHEL:
https://access.redhat.com/solutions/488043

Database on RHEL
https://access.redhat.com/solutions/332623