HT on the new Prescott processor

[ronnyzhang]

Hi, I'm interested in the newly anounced Prescott processor( Pentium 4 extream edition with HT).

But I wonder what's the difference between prescott's HT technology and its original versionbuilt in Pentium 4.

I have been looking through this website, and found these words:

Improved Hyper-Threading Technology, including important enhancements to this innovation that make a single processor act like multiple processors to the operating system

But what is the important enhancements? It seems that Intel hasn't posted it on the site. Maybe someone here can help me. Thanks.

Message Edited by RonnyZhang@hotmail.com on 01-15-2004 07:02 AM

Message Edited by RonnyZhang@hotmail.com on 01-15-2004 07:05 AM

[TimP]

Several changes in Prescott are intended to improve HT performance. For example, the increase in number of Write Combine buffers from 6 to 8 would permit HT threaded applications to write efficiently into 3 array sections within a single loop, where 2 was the previous limit.

[TimP]

For publicity purposes, they may be counting other changes since the original P4, such as the alleviation of the 64K aliasing problem, which could bea severe handicap to HT applications. Now, if you neglect to offset your stacks in a Windows application, for example, you should not immediately run into the aliasing problem. The aliasing problem now would occur with 1MB address intervals, so should not be so pervasive. Increased cache size also is likely to improve the effectiveness of HT in many applications.

[isn-removed938]

Yes,this is one improvement, but not a significant change for just increasing in number of Write Combine buffers from 6 to 8.

Is there a technical paper or manual telling us the architectual improvement of Precott's HT relative to P4?