disable the hyper threading ON Linux

[Jim Nelson]

vadim wrote:
> Same here - BIOS is the only way to disable it. On a personal note, an 
> HT CPU performs faster than non HT CPU - tried that a few years back.
> -V
> 

On the other hand, it has been demonstrated to have security problems - leaking 
private keys through ineffective L1 and L2 cache protection across threads.


There was a big stink about it a couple of years ago - see:

http://kerneltrap.org/node/5103

I turn HT off on machines when I find it - most HT machines are a couple of 
years old, and newer multicore machines don't have the same vulnerability.

> David Chait wrote:
>> I'm fairly certain that this is only done via the machine Bios, not the OS.
>>
>> -David
>>
>>
>> Santhosh kumar wrote:
>>> Some one guide me how to disable the hyper threading on Dell 2650? I 
>>> am running rhel 3 update 6. Is there any way I can do this 
>>> modification from the OS level.
>>>
>>>  
>>>
>>> Thanks in advance
>>> Santhosh
>>>
>>>
>>> ------------------------------------------------------------------------