Slashdot Mirror
Linux Kernel Benchmarking: 2.4 vs. 2.6-test
frooyo pastes from kerneltrap: "Cliff White recently posted some re-AIM multiuser benchmark results comparing the stable 2.4.23-pre5 kernel against the 2.6.0-test5 and 2.6.0-test5-mm4 development kernels. In his conclusion he makes reference to earlier scheduler tests posted by Mark Wong saying, "Short summary: we mostly rock.""
I run 2.4.22 at work and 2.6.0-testX at home. The 2.6.0test(vanilla) series feel much more responsive, especially in X. I have not done any real benchmarks of my systems, but after working with 2.4 all day 2.6 seems to fly.
Just my observation
-the_crowbar
Have you read the Moderator Guidelines
Since it seems your running debian and all those cpu intensive operations are also hd intensive operations have you checked hdparm -d /dev/hda . I know it is simple but it is so simple that I forgot to check for about a month. Debian appears to have dma off by default.
Devphaeton, you hit the nail on the head about 2.6.0. Its main advantage over 2.4.x (for this luser anyway) is the smoother multitasking even on a uniprocessor system. I'm running a tweaked 2.6.0-test5 on my laptop, and jobs that would make 2.4.x unusable are barely detectable (from the standpoint of moving the mouse around, typing up slashdot articles, and the like).
:-)
Of course, the ACPI support and swsusp doesn't hurt either
a quad cpu more performant than 4 * single cpu?
Odd but not impossible.
For example, if in the single cpu config the processes are doing a lot of memory-cache missed then having 4 cpus (with 4 times more the amount cache) could reduce the number a cache misses and so could make the quad configuration more than 4 times faster.
The same reason could explain why 2 cpus are not faster than one: if 2 caches are not large enough and if the processes have a very bad locality then you may get as much cache misses with the dual cpu system than with the single cpu system.