OK, in response to a recent Phoronix article that purports to show how amazing the Panda Board is compared to a 2.5 year old single-core Atom (see TR thread here: http://techreport.com/news/23512/tuesday-shortbread
) I have decided to fight fanboism with fact. I went out and installed the Phoronix Test Suite on my Arch Linux notebook and started doing some benchmarks of my own. I have preliminary results posted here and will update the thread as I get the chance to run more tests.
In one corner: The numeric results published by Phoronix from the article in question for the Panda Board (released late 2011 and still representing a very high-end ARM development board) using a dual-core Cortex A9 clocked at 1GHz a piece.
In the other corner: My four year old notebook (purchased August, 2008) with a Core2 Duo P8400 (dual core with 2.26GHz max clock but see explanation below below
).BUT WAIT YOU SAY THAT'S NOT FAIR TO ARM!!
Oh but it is.. you see while my notebook theoretically has two cores and a higher clock speed, I disabled one core and forced the CPU to a lower clock speed using the following commands:
1. Disable the second core:
sudo sh -c "echo 0> /sys/devices/system/cpu/cpu1/online"
2. Force the one remaining CPU core into permanent power-saving mode stuck at 800 MHz with no ability to boost back to full-speed:
sudo sh -c "echo powersave /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor"
Output of /proc/cpuinfo taken during the benchmark with single CPU pegged at 100%:
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Core(TM)2 Duo CPU P8400 @ 2.26GHz
stepping : 6
microcode : 0x60ccpu MHz : 800.000 <-- This is the actual Mhz of the single core taken during the benchmark
cache size : 3072 KB
physical id : 0
siblings : 1
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc up arch_perfmon pebs bts rep_good nopl aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 lahf_lm dtherm tpr_shadow vnmi flexpriority
bogomips : 4524.72
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
Here is the first result from C-Ray (a multi-threaded benchmark that has favored the Panda Board), more to follow:
1. Phoronix published results: 875.76 seconds (14 minutes 35.76 seconds) to completion (less is better).
2. Single-core Core 2 at 800 MHz: 746.59 seconds (12 minutes 26.59 seconds) to completion (3 run average, 743.588 minimum, 751.047 maximum)
3. Winner: One core of the Core 2 at 800 Mhz
Margin of win: 2 minutes 9.17 seconds (Core 2 is 14.7% faster compared to A9 posted times).
Before I hear how using a 4 year old single underclocked x86 core in multithreaded benchmarks against a higher-clocked multi-core ARM system is somehow cheating in Intel's favor:
1. This test was run from a full-blown KDE 4.9 desktop running on the notebook during the benchmarks because I was too lazy to kill the X-server and drop to the command prompt.
2. Unlike the Panda Board I slapped the Phoronix suite on a boring standardized Arch Linux system and was running the first benchmark in about 15 minutes. No running out trying to optimize every single library with some magical "hardfp" branch and trying to perform brain surgery with exotic GCC options for every test.
3. P.S. --> While I was running these benchmarks, I was also SSHing in to the laptop to collect data and I even took a screenshot (below). Try running KDE 4.9 on the A9 board and taking screenshots DURING THE BENCHMARK RUN
and see what kind of timing hit you take.
Edit: Here is a link to a whole album of screenshots I'll be taking. The yakuake terminal is taken in the middle of the second c-ray run, the other two are screenshots of the official Phoronix test suite benchmark results in the web browser on the notebook: https://picasaweb.google.com/1026166348 ... directlink