atom feed5 messages in com.googlegroups.beagleboard[beagleboard] Floating Point Performance
FromSent OnAttachments
rtp...@comcast.netOct 21, 2008 2:02 pm 
Måns RullgårdOct 21, 2008 2:13 pm 
Yusuf Caglar AKYUZOct 22, 2008 12:14 am 
Koen KooiOct 22, 2008 1:19 am 
Måns RullgårdOct 22, 2008 1:29 am 
Subject:[beagleboard] Floating Point Performance
From:rtp...@comcast.net (rtp@comcast.net)
Date:Oct 21, 2008 2:02:18 pm
List:com.googlegroups.beagleboard

Hello Folks, I built nbench for my beagleboard and compiled with flags that one would be
led to believe would enable floating point operation:

-mcpu=cortex-a8 -mfloat-abi=softpf -mfpu=neon

My nbench results are below (just to share around). My question is... are
these results consistent with what folks expect? Why is the FP performance still
so low even with the floating point hardware "engaged"? Any thoughts? Compiler
maturity? What would one expect the BB to achieve on simple FP benchmarks like
this?

root@beagleboard:~/Tools/nbench-byte-2.2.3# ./nbench

BYTEmark* Native Mode Benchmark ver. 2 (10/95) Index-split by Andrew D. Balsa (11/97) Linux/Unix* port by Uwe F. Mayer (12/96,11/97)

TEST : Iterations/sec. : Old Index : New Index : : Pentium 90* : AMD K6/233* --------------------:------------------:-------------:------------ NUMERIC SORT : 236.56 : 6.07 : 1.99 STRING SORT : 23.696 : 10.59 : 1.64 BITFIELD : 8.0473e+07 : 13.80 : 2.88 FP EMULATION : 50.999 : 24.47 : 5.65 FOURIER : 886.67 : 1.01 : 0.57 ASSIGNMENT : 3.3465 : 12.73 : 3.30 IDEA : 583.89 : 8.93 : 2.65 HUFFMAN : 289.46 : 8.03 : 2.56 NEURAL NET : 0.95786 : 1.54 : 0.65 LU DECOMPOSITION : 37.915 : 1.96 : 1.42 ==========================ORIGINAL BYTEMARK RESULTS========================== INTEGER INDEX : 11.026 FLOATING-POINT INDEX: 1.450 Baseline (MSDOS*) : Pentium* 90, 256 KB L2-cache, Watcom* compiler 10.0 ==============================LINUX DATA BELOW=============================== CPU : L2 Cache : OS : Linux 2.6.26-omap1 C compiler : gcc version 4.3.1 (GCC) libc : libc-2.6.1.so MEMORY INDEX : 2.499 INTEGER INDEX : 2.957 FLOATING-POINT INDEX: 0.804 Baseline (LINUX) : AMD K6/233*, 512 KB L2-cache, gcc 2.7.2.3, libc-5.4.38 * Trademarks are property of their respective holder.