Per, On Wednesday 31 May 2006 07:16, Per Jessen wrote:
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Hyperhreading is different - only one processor that pretends to do more things at the same time :-)
The difference is more a matter of degree. In an HT CPU there is less duplicated internal machinery. A dual-core CPU has two full CPUs that operate largely independently. In the current dual-core chips, I believe, there is a single, shared level-2 cache. The HT CPUs don't double all of the CPU's hardware, but they still hold two full sets of the CPU's internal state and a good-sized chunk of the processing machinery, making possible both (some) concurrent processing and faster context switching between the processes or threads that occupy those register sets than on a conventional single CPU. It seems HT CPUs were just a transitional state between older single CPU chips and modern multi-core chips.
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/Per Jessen, Zürich
Randall Schulz