Speex dev - Dec 2006 - Big GAP of speex MCPS on arm CPU and RVDS simulator

Hi all Speexers,

I've done some optimization to current SVN fixed-point on ARM9E platform.

If the RVDS simulator gives the MCPS(Million Cycle Per Second)  value A,
then actual MCPS on real CPU will be around 2*A.

I don't know what cause the big gap between the simulator and real CPU.

What do you think?

BR,

Lianghu
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Well, you probably have a mismatch between the CPU and the simulator.
Some things that can have a high impact are:
- MHz (or course!(
- Speed of multiplier (ARM cores can be really slow)
- Speed/size of cache. Write-through can be much slower than write-back.

	Jean-Marc

lianghu xu a ?crit :
> Hi all Speexers,
> 
> I've done some optimization to current SVN fixed-point on ARM9E
platform.
> 
> If the RVDS simulator gives the MCPS(Million Cycle Per Second)  value A,
> then actual MCPS on real CPU will be around 2*A.
> 
> I don't know what cause the big gap between the simulator and real CPU.
> 
> What do you think?
> 
> BR,
> 
> Lianghu
> 
> 
> ------------------------------------------------------------------------
> 
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