On Fri, 07 Nov 2003 14:45:39 +0000, Martin <ml_news@ddnospamddml1dd.co.uk.dd> wrote:
: Stagger Lee wrote:
: > On Fri, 07 Nov 2003 02:08:50 +0000, Martin <ml_news@ddnospamddml1dd.co.uk.dd> wrote:
: > : Stagger Lee wrote:
: > : [...]
: [...]
: > 
: > I am amazed at your own arrogantly profound ignorance.
: > 
: > : 
: > : However, to be brief:
: > : 
: > : 'Hyperthreading' is an Intel marketing term for a very old trick of 
: > : keeping the multiple internal CPU functional units simultaneously busy.
: > : 
: > : To the OS, the one physical CPU appears to be two distinct CPUs. Hence, 
: > : if only one process is running, the best reported utilisation is 50% (or 
: > : rather, 100% for one of the two hyperthread CPUs).
: > : 
: > : You can run a second process to keep the second 'hyperthread' CPU busy.
: >  
: > That just isn't right.  I don't know where this non-cited information
: > was obtained, but my original citation (look it up in the thread
: > yourself) explains why the *entire* CPU will be devoted to the task at
: > hand, contrary to your incorrect explanation.  It is an intrinsic part
: > of the hyperthreading algorithm that the virtual CPU units all
: > coalesce into one unit when that is the optimal configuration.
: > Hyperthreading *does not* split the CPU up into some minimum number of
: > virtual CPUs which is larger than one.
: [...]
: 
: 
: Insults aside. You are very misinformed.
: 
: This non-cited information is elementary Computer Science!
: 

Better tell Intel about your theories.  From the Intel Technology Journal,
Vol 6, Issue 1:

"A third goal was to allow a processor running only one active
software thread to run at the same speed on a processor with
Hyper-Threading Technology as on a processor without this capability.
THIS MEANS THAT PARTITIONED RESOURCES SHOULD BE RECOMBINED WHEN ONLY
ONE SOFTWARE THREAD IS ACTIVE." [Emphasis mine.]

As I said, the hyperthreading algorithm is implemented intellegently
enough that the processor does not sit there with half of its
architecture inactive when it has only a single task (thread) to
process.  As my first citation indicated, and AS THE INTEL LITERATURE
STATES, the virtual processors become one and do not remain partitioned.

Let me assure you that this is my final response to you on this
subject.  It is clearly quite pointless to further discuss technical
matters with you.

<PLONK>