We have some concern about performance measurements we have
made.
Searching the TI website we found the following document on
Cortex A8 performance
http://processors.wiki.ti.com/index.php?title=Cortex-A8_Features#OMAP_ARM_Cores_Performance_Dhrystome_V2.1
Which claims 2.01 Dhrystone V2.1 DMIPS per MHz. Since we are
running our OMAP at 500 MHz we should expect about 1005 DMIPS.
We obtained the "official" Dhrystone V2.1 benchmark source code
from
http://www.netlib.org/benchmark/dhry-c
and compiled and ran it. We converted the Dhrystone figure to
DMIPS by dividing by 1757 which we understand to be the standard
conversion.
On our OMAP 3525 running LynxOS SE at 500 MHz and compiling with
LynxWorks cross compiler we get 237.1 DMIPS
To compare we used an older board using the OMAP 3430 (that we
used prior to 3525 availability) under Monta Vista mobile Linux
and using their cross-compiler and got 258.7 DMIPS.
We realize that Dhrystone measurements will vary some due to
differences in compilers and OSs but would not expect our
getting around 25% of TI's figure.
Can you suggest why we might be getting such drastically lower
figures?