Hyperthreading is not active

[Andywlman1]

Hi,

The ESXi 5.5 (Build 9919047) running on Dell R710, and I enabled hyperthreading in Bios, however, ESXi show the status is "Disable (Enable on restart) (Not Active)", remark show "host BIOS must enable hyperthreading before the host can activate the feature., I just confuse that anything i missing?

Thanks,

Andy

[scott28tt]

Moderator: Thread moved to the ESXi area.

[scott28tt]

Note that if you are running anything like production workloads you should consider using at least 6.5 since no older versions of ESXi now receive support or updates.

[amohammadimir]

Didn't you enable VMKernel.Boot.hyperthreadingMitigation advanced option by any chance? If yes, disable it then reboot and check again.

[Andywlman1]

yes, i enable vmkernel.boot.hyperthreadingmitigation in advanced option, then i try disable and reboot, and the same result come up.

[Andywlman1]

Thank you.

[IRIX201110141]

Please tell us more about the Intel XEON you have in this server because the entry level CPUs doesnt have HT.  For sure there is an BIOS option and also the ESXi setting but the Hardware doesnt support it.

Regards,
Joerg

[Andywlman1]

Hi, Joerg,

The server using Xeon X5670, which is support Hyperthreading Technology.

for the ESXi, i tried enable / disable option on hyperthreadingmitigation and hyperthreading and reboot, but the result are the same, Not Active.

Regards,

Andy

[IRIX201110141]

Yes the Intel X5670 comes with HT support.

We are a Dell shop and have plenty of R710 in the past.  In the Dell BIOS they dont use the term "Hyperthreading" and name it "logical processor" instead. So please check this.

On paper the R710 with x56xx (Westmare) supporting up to ESXi 6.0 but also 6.5/6.7 will run.  You cant install/run 6.7 on a x55xx (Nehalem) based CPU.

Dell removed all Update ISO and also the direct download through LCC isnt working anymore. Consider to check for BIOS updates manually by visiting dell.com/support. They released Spectre/Meltdown related BIOS upgrades.

Regards,

Joerg

[vmkfix-SSA]

I followed below article to resolve the issue 

https://vmkfix.blogspot.com/2023/04/hyperthreading-not-enabling-on-esxi.html?m=1