Well, what the OS thinks is really irrelevant w.r.t. Hyper-Threaded processors.

Hyper-Threading only gives 5% performance improvement over a single
thread, on CPU-bound activities. A thread is much, much less than a
core.

That actually explains why you only see one or two bars with lots of activity.

To quote one of my colleagues from Redwood Shores:

"Yes. Hyperthreading only works if there are lots of L2 cache misses.
Then the CPU can work on the pretend CPU's work while waiting. But if
there were no cache misses then there would be zero benefit to HT. So
the tighter your code is the less HT works.

HT is basically a fraud. You are seeing exactly what you will with
almost anu software, not just with TimesTen. If you get even 5%
improvement then you did good. No one should expect much more."




On 10/5/07, Michael Tinsay <[EMAIL PROTECTED]> wrote:
..
> I have a server that has a dual-core, HT-enabled processor.  Ubuntu says it
> has 4 processors.  htop shows 4 bars for processors, but most of the time
> only one or two have activity.
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