At 10:34 AM 8/18/2004, you wrote:
> >HT only works in XP or 2003 Server
>
>This is not correct. HT "works" with any multi-processor build of Windows
>NT-based OS. With XP and 2003 it works BETTER because those systems know
>the difference between a virtual processor and a physical processor. NT
>and 2000 will not schedule the virtual processors as efficiently.
Well, your're wrong, there are numerous technical articles about this,
Here is Intel's HT support page
-------------------------------------------------------------------------------------------------
http://www.intel.com/support/platform/ht/os.htm?iid=ipp_htm+os&
Microsoft* Windows* Operating System Desktop Based PCs
The following desktop operating systems include optimizations for HT
Technology and are currently eligible to carry the new IntelŪ PentiumŪ 4
Processor with HT Technology logo:
Microsoft* Windows* XP Professional Edition
Microsoft* Windows* XP Home Edition
The following desktop operating systems are not recommended for use with
Hyper-Threading Technology. If you are using one of the following desktop
operating systems, it is advised that you should disable Hyper-Threading
Technology in the system BIOS Setup program:
Microsoft Windows 2000 (all versions)
Microsoft Windows NT* 4.0
Microsoft Windows Me
Microsoft Windows 98
Microsoft Windows 98 SE
-------------------------------------------------------------------------------------------------
Microsoft does say you can have limited support with Windows 2000 Advanced
Server. But I have tried this, and real world use has shown that it isn't
worth the effort. Note that XP Home supports HT, but not SMP.
But lets look at some real world facts. I am running two HT PCs here. One
is a P4 3.0 Ghz @ 800Mhz with HT and the other is a Dual Xeon 3.06 Ghz @
533Mhz with HT. Both computers multi boot Windows 2000 Pro SP4, and Windows
XP Pro SP1. On both computers Windows XP employs HT. In XP PRO, Device
Manager, on the Xeon, I see four processors. In device manager on the P4 I
see two processors. In taskmaster performance tab on the Xeon I see four
processors. In 2000 PRO on the Xeon I see two processors in both device
manager and taskmanager while on the P4 in Windows 2000 PRO I see a single
processor.
> >applications must be written to support HT
>
>This is not necessary to experience improved performance. Windows NT is a
Again you wrong. I don't think you understand how HT = Hyperthreading and
SMP = Symmetric Multi Processor works. In order to take advantage of multi
processors, the operating system must support SMP and or HT. NT4, Windows
2000 and XP PRO support SMP but only XP PRO supports SMP and HT. XP Home
supports HT but has no support for SMP. In addition, while you will have
some performance benefit, to the system, as a whole, while running SMP, or
HT, in order to fully benefit from SMP, and or HT, the individual
application, must be coded to take advantage of it. The performance
difference from a supported application can be quite dramatic. But these
applications, at the desktop level, are few.
The same is true of HT. In the first place, the operating system doesn't
treat HT as a virtual processor. It treats it as if it is a real physical
processor. As far as the computer is concerned, on a single processor HT
system, you have a Dual processor SMP setup. As HT becomes more popular you
will see more and more applications coded to support it.
If you doubt this take a look at the Ulead Studio Video web page. Under
features you will find "support " for HT. And my own test shows this to be
true with that application. I can boot into Windows 2000 and encode a video
file and then do the same in XP PRO. The difference is 12 percent increase
in speed in XP PRO, which is right in line with what Intel claims, Intel
claims10 to 20 percent in supported software.
An application that is coded to take advantage of both SMP, and HT is the
latest version of TMGenc. Encoding times are startling when running on my
dual Xeon with HT.
>ulti-tasking OS that can do more than one thing at a time and when multiple
>processes or threads are active at once they can run on different virtual
>processors.
These are not virtual processors. Intel designed HT to multi thread, and XP
Pro sees HT as two physical processors.
http://www.intel.com/technology/hyperthread/index.htm
"Hyper-Threading Technology provides thread-level-parallelism (TLP) on each
processor resulting in increased utilization of processor execution resources."
and
"This technology is largely invisible to the platform. In fact, many
applications are already multi-threaded and will automatically benefit from
this technology. However, multi-threaded applications take full advantage
of the increased performance that Hyper-Threading Technology has to offer,
allowing users will see immediate performance gains when multitasking.
Today's multi-processing aware software is also compatible with
Hyper-Threading Technology enabled platforms, but further performance gains
can be realized by specifically tuning software for Hyper-Threading
Technology. This technology complements traditional multi-processing by
providing additional headroom for future software optimizations and
business growth."
Rode
The NOSPIN Group
http://freepctech.com
>The result will be overall greater performance than a non-HT
>processor of the same speed. Granted, it's not that much greater, but
>Windows will keep both "processors" going.
>
>Carl
Do you want to signoff PCBUILD or just change to
Digest mode - visit our web site:
http://freepctech.com/pcbuild.shtml
|
