single threaded vs multi-threaded tests?

[jgregnash]

The only thing I could find in the forum directly related to the subject above was posted by you on Jan 2003:

"Most of the tests in PerformanceTest are single threaded. This means that only a single CPU will be used at a time. This is similar to a lot of commonly used applications, which are also single threaded."

Is this still the case? If so I don't understand why my "old" 3.6GHz Pentium D Dual Core (Dell Precision 380) is ~x4 slower on integer math than the benchmark 3.5GHz "QX6800 Intel Core 2 2930 BL6710" with 4 cores.

If (hypothetically) your tests are truly single threaded, all other things being equal, wouldn't the "integer math" (which is what my application needs) rating be directly proportional to clock speed?

Greg Nash

[David (PassMark)]

A lot has changed since 2003.

All the CPU tests are multi-threaded (multi-process to be precise). So they can take advantage of dual core, quad core and multiple CPU scenarios.

The other tests (like the disk test and 2D test) are single threaded.

But regardless of being multi-threaded or not, CPU performance is determined by more than just the clock speed. For example all the new Intel Core 2 CPU's are faster than the old Pentiums, but the Pentiums had a higher clock speed.

[jgregnash]

single process vs multi process

Could you tell me which of the CPU intensive tasks are single process? For example on most of the 2D graphics tests, the quad core I mentioned is several times faster than my dual core. However, strangely for the "2D-Shapes" my dual core is ~x3 faster than the quad core? I'm trying to make sense of this.

Greg Nash

[David (PassMark)]

...which of the CPU intensive tasks are single process?

All the CPU tests are multi-threaded. All the other tests are single threaded. At least from the applications point of view, we can't vouch for what happens in the O/S and device drivers.

Differences in the 2D video results is more likely to be the result of 1) your video cards 2) video card device drivers and 3) system configuration.