Messages in this thread | | | From | "Scott Robert Ladd" <> | Subject | HT Benchmarks (was: /proc/cpuinfo and hyperthreading) | Date | Mon, 16 Dec 2002 10:44:34 -0500 |
| |
Måns Rullgård wrote: > It's easy to write a program that displays any number of graphs > vaguely related to the system load. How do we know that the > performance meter isn't lying?
We don't.
All I can say is that the performance meter seems (note the weasel-word) proper when running Win2K SMP on a dual PIII-933 box at one of my client sites. However, such experience does *not* guarantee that WinXP is reporting valid numbers for a P4 with HT.
Here's a little test I ran this morning, now that my new system is operational. My benchmark is a full "make bootstrap" compile of gcc-3.2.1, with and without the - j 2 make switch that enables two threads of compilation. Using the 2.5.51 SMP kernel, I see the following compile times:
SMP w/o -j 2: 28m11s "nosmp" with -j 2: 27m32s SMP with -j 2: 24m21s
HT appears to give a very tiny benefit even without an SMP kernel -- and *with* an SMP kernel, I get a 16% improvement in my compile time. That pretty much matches my expectation (i.e., a HT processor is *not* equal to dual processor, but it *is* better than a non-HT processor).
Just some food for collective thought.
..Scott
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |