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Hello all, 
i have written a channel class, which collects data from (file) sources and

copies it to a buffer. Jack will get this buffer and put it into his streams.

So far, I think, this is a normal design with the following code
for (unsigned int n = 0; n < nframes; ++n)

{

	   pBuffer[n] += pFrames[n];

	   pBuffer[n]  *= volume;

}
i know, it's not really optimized. But it works as an example. as you can

think, pBuffer and pFrames are float* and volume is also a float. 
now it happens, when the volume is 0, after 3-5 seconds, the CPU will run into

100%. 
a workaround is the following before the loop 
	if(volume < 0.0000001)

		volume = 0.0000001;
But i try to understand, what happens here. Is the compiler overoptimizing

zeros.

compiler is:  $g++ -v

Using built-in specs.

Target: i486-linux-gnu

Configured with: ../src/configure -v --enable-languages=c,c++,fortran,objc,obj-

c++,treelang --prefix=/usr --enable-shared --with-system-zlib --

libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --

enable-nls --program-suffix=-4.1 --enable-__cxa_atexit --enable-clocale=gnu --

enable-libstdcxx-debug --enable-mpfr --with-tune=i686 --enable-

checking=release i486-linux-gnu

Thread model: posix

gcc version 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)
what puzzles me is, that this doesn't happen on my double core system. 
Any ideas. Thanks c~
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p, li { white-space: pre-wrap; }Hello all,

i have written a channel class, which collects data from (file) sources and copies it to a buffer. Jack will get this buffer and put it into his streams.

So far, I think, this is a normal design with the following code

for (unsigned int n = 0; n < nframes; ++n)

{

	   pBuffer[n] += pFrames[n];

	   pBuffer[n]  *= volume;

}

i know, it's not really optimized. But it works as an example. as you can think, pBuffer and pFrames are float* and volume is also a float.

now it happens, when the volume is 0, after 3-5 seconds, the CPU will run into 100%.

a workaround is the following before the loop

	if(volume < 0.0000001)

		volume = 0.0000001;

But i try to understand, what happens here. Is the compiler overoptimizing zeros.

compiler is:  $g++ -v

Using built-in specs.

Target: i486-linux-gnu

Configured with: ../src/configure -v --enable-languages=c,c++,fortran,objc,obj-c++,treelang --prefix=/usr --enable-shared --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --enable-nls --program-suffix=-4.1 --enable-__cxa_atexit --enable-clocale=gnu --enable-libstdcxx-debug --enable-mpfr --with-tune=i686 --enable-checking=release i486-linux-gnu

Thread model: posix

gcc version 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)

what puzzles me is, that this doesn't happen on my double core system.

Any ideas. Thanks c~

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