EmbeddedRelated.com
Forums

reason for difference in MIPS between simulator and Board

Started by swami.kmb July 24, 2008
Dear Friends,
I am porting eAAC decoder in ARM926EJ-S (ARM9E core)
The MIPS measurement in simulator and onboard are not same.
MIPS onboard is higher than in simulator(4 to 6 MIPS)
can anyone tell me what's the reason behind this?
MIPS are measured onboard with cache disabled(at this point,will be
enabled later)

The reason i think of:
1.Stack/heap/bss section/state variables are not getting fitted in
internal memory

2.because of page fault?if so how can i avoid it?(ARM926EJ-S has MMU)

3.Is there any way to modify the linker file for ARM,i feel stack/heap/bss
section is not getting fitted in internal mem

Finally,
will there be any difference in MIPS, when the project is built in debug
and release mode?



Op Thu, 24 Jul 2008 08:09:14 -0600 schreef swami.kmb <swami.kmb@gmail.com>:
> Dear Friends, > I am porting eAAC decoder in ARM926EJ-S (ARM9E core) > The MIPS measurement in simulator and onboard are not same. > MIPS onboard is higher than in simulator(4 to 6 MIPS) > can anyone tell me what's the reason behind this?
Because a simulator simulates an entire processor on another processor. The clocks are probably not the same, and maybe the simulator clock isn't even constant.
> MIPS are measured onboard with cache disabled(at this point,will be > enabled later) > > The reason i think of: > 1.Stack/heap/bss section/state variables are not getting fitted in > internal memory
Is there a difference between the internal memories?
> 2.because of page fault?if so how can i avoid it?(ARM926EJ-S has MMU)
There should be a way to detect and log page faults.
> 3.Is there any way to modify the linker file for ARM,i feel > stack/heap/bss section is not getting fitted in internal mem
Use a text editor.
> Finally, > will there be any difference in MIPS, when the project is built in debug > and release mode?
That depends on the differences between debug and release mode. -- Gemaakt met Opera's revolutionaire e-mailprogramma: http://www.opera.com/mail/