Re: [PATCH 0/4] i386 - pte update optimizations

Keir Fraser
2007-04-13T11:31:32Z

On 13/4/07 13:27, "Andi Kleen" <andi@firstfloor.org> wrote:

>> LOCKed instruction suck really badly on the netburst microarchitecture (like
>> factor of 10x, or not far off). I think it's probably because of their side
>> effect of serialising memory accesses, causing horrible pipeline stalls.
>
> Unfortunately they tend to be HyperThreaded usually (except for early ones
> and Celerons) and need the LOCK anyways.

Fair point, although quite a few people disable HT.

-- Keir