[Beowulf] Intel CPU design bug & security flaw - kernel fix imposes performance penalty

Kevin Van Workum vanw+beowulf at sabalcore.com
Wed Jan 3 12:29:47 PST 2018


Intel's response:
https://www.streetinsider.com/Corporate+News/Intel+%28INTC%29+Responds+to+Security+Research+Findings/13648696.html

On Wed, Jan 3, 2018 at 12:57 PM, Joe Landman <joe.landman at gmail.com> wrote:

> Looks like it will respond to a 'nopti' boot option (at least the patches
> I've seen from 4-Dec)
>
>
>
> On 01/03/2018 12:57 PM, Ellis H. Wilson III wrote:
>
>> On 01/03/2018 12:47 PM, Lux, Jim (337K) wrote:
>>
>>> I suppose the down side is that if they do kernel mods to fix this
>>> for the 99.9%, it adversely affects the performance for the 0.1%
>>> (that is, us).
>>>
>>
>> We've been discussing this extensively at my workplace, and the
>> overwhelming expectation is that at least in Linux the fix should be
>> configurable such that those operating in non-multitenant systems (such as
>> scale-out storage appliances) can disable it.
>>
>> If this ends up not being the case, I would expect it in the short-term
>> to lock us out of upgrading to newer kernels where the fix and resultant
>> overheads come into play until we're on newer CPUs where the architecture
>> deficiency is resolved.  This latter part (the expectation of Intel fixing
>> it in their newer HW) is all the more reason I'm inclined to believe the
>> fix will be delivered as a tunable.
>>
>> Best,
>>
>> ellis
>>
>>
> --
> Joe Landman
> e: joe.landman at gmail.com
> t: @hpcjoe
> w: https://scalability.org
> g: https://github.com/joelandman
> l: https://www.linkedin.com/in/joelandman
>
>
> _______________________________________________
> Beowulf mailing list, Beowulf at beowulf.org sponsored by Penguin Computing
> To change your subscription (digest mode or unsubscribe) visit
> http://www.beowulf.org/mailman/listinfo/beowulf
>



-- 
Kevin Van Workum, PhD
Sabalcore Computing Inc.

-- 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.beowulf.org/pipermail/beowulf/attachments/20180103/33479584/attachment.html>


More information about the Beowulf mailing list