the next sdk release is suppose to have a Dalvik JIT i nit doubling speed/performance..
I am in the same boat, have image processing projects but am holding off until JIT is out.. On Jan 6, 11:49 am, niko20 <[email protected]> wrote: > You'll have to use the NDK and write some native C code to do your > math, that will speed it up a lot. And use fixed point if you need > floats. > > -niko > > On Jan 6, 11:08 am, Biosopher <[email protected]> wrote: > > > > > I'm writing a processing intensive digital sound processing app > > (requires numerous (50,000) Fast Fourier Transforms - FFT). This > > challenge led me to perform basic performance tests of Android running > > on an HTC Hero. > > > The results show the Dalvik VM to be >20 times slower than a modern > > JIT-enabled JVM running J2ME and 25-50 times slower than a C program > > performing the same operations on a similarly powered mobile phone. > > > For example, this simple iteration over an empty method 2 million > > times takes 1.4 seconds even though it doesn’t do anything. The same > > iteration is performed in milliseconds by a C program and about 100ms > > on a modern JVM > > > public void performanceTest1() { > > for (int i = 0; i < 2000000; i++) { > > emptyMethod(); > > } > > > } > > > private int emptyMethod() { > > return 0; > > > } > > > Doing something a little more complex like calculating the imaginary > > component of a complex conjugate 2 million times takes 3.2 seconds. > > Again, this takes milliseconds on other mobile phones running J2ME or > > C. > > > public void performanceTest2() { > > for (int i = 0; i < 2000000; i++) { > > int a = 5; > > int b = 5; > > int c = 5; > > int x = 5; > > int y = 5; > > > y = ((a >> 16) * ((c << 16) >> 16)) + (((a & 0X0000FFFF) * > > ((c << > > 16) >> 16)) >> 16); > > y = -y; > > y += ((b >> 16) * (c >> 16)) + (((b & 0X0000FFFF) * (c >> > > 16)) >> > > 16); > > } > > > } > > > Has anyone else been able to overcome these performance issues of > > Android?
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