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programming:instruction-timings [2006/12/13 18:58]
cyril created
programming:instruction-timings [2013/09/19 16:41] (current)
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 ===== Proceeding ===== ===== Proceeding =====
  
 +FIXME
  
 ===== Summary of results ===== ===== Summary of results =====
 +
 +Depending on machines, floating point operations can be a lot slower than integer operations, or as fast, or even faster.
 +
 +Multiprocessor configs and multicore processors doesn't bring any improvement on these tests, and that's normal. Indeed in order to exploit it you have to have several threads, which is not the case here, and not the purpose.
 +
 +
 +
  
  
 ===== All results ===== ===== All results =====
  
 +All timings are given in nanoseconds (ns).
  
-^  Title  ^  Code  ^  Cyril_F  ^  Cyril_P  ^  cJ_F  ^  cJ_P   Infomob  ^  Almighty  ^  PC104  ^+^  Title  ^  Code  ^  Cyril_F  ^  Cyril_P  ^  cJ_F  ^  MacGyver   Infomob  ^  Almighty  ^  PC104  ^
 ^  RGB -> Y Conversion  ^^^^^^^^^ ^  RGB -> Y Conversion  ^^^^^^^^^
-|Float  |''imgg[k2++] = (0.299*img[k++] + 0.587*img[k++] + 0.114*img[k++]);''  |  175  |  |  |  6.09 ??!  |  20.8  |  12.6  |  84.3  | +|Float  |''imgg[k2++] = (0.299*img[k++] + 0.587*img[k++] + 0.114*img[k++]);''  |  175  |  18.8   22.1   6.09 ??!  |  20.8  |  12.6  |  84.3  | 
-|Integer  |''imgg[k2++] = (19595*img[k++] + 38470*img[k++] + 7471*img[k++]) >> 16;''  |  91.1  |    |  25.1  |  4.03  |  153  | +|Integer  |''imgg[k2++] = (19595*img[k++] + 38470*img[k++] + 7471*img[k++]) >> 16;''  |  91.1  |  8.92  |  8.30  |    |  25.1  |  4.03  |  153  | 
-|Shift1 |''imgg[k2++] = (img[k++]>>2 + img[k]>>1 + img[k++]>>3 + img[k++]>>3);''  |  50.4  |  |  |  |  10.6  |  5.97  |  29.3  | +|Shift1 |''imgg[k2++] = (img[k++]>>2 + img[k]>>1 + img[k++]>>3 + img[k++]>>3);''  |  50.4  |  9.75   11.2   |  10.6  |  5.97  |  29.3  | 
-|Shift2 |''imgg[k2++] = (img[k]>>2 + img[k++]>>4 + img[k]>>1 + img[k++]>>4 + img[k++]>>3);''  |  56.7  |  |  |  |  11.7 |  6.65  |  43.4  |+|Shift2 |''imgg[k2++] = (img[k]>>2 + img[k++]>>4 + img[k]>>1 + img[k++]>>4 + img[k++]>>3);''  |  56.7  |  12.5   13.3   |  11.7  |  6.65  |  43.4  | 
 +^  Array indexes  ^^^^^^^^^ 
 +|    |    |    |    |    |    |    |    |    | 
 + 
 + 
 + 
 +===== Configs used ===== 
 + 
 + 
 + 
 + 
 + 
 + 
 +==== Summary ==== 
 + 
 +^  ^  CPU  ^  Frequence  ^  Arith. Coproc.  ^  Bogomips  ^  FPU  ^  Cache  ^  GCC Version 
 +^Cyril_F  |Celeron Mendocino  |500 MHz | |1003  |yes  |128 KB|3. | 
 +^Cyril_P  |AMD64 3000+  |1.8 GHz  | | 3593 |yes |1024 KB |4.1.1 |  
 +^cJ_F  | AthlonXP 2400+ |2.0 GHz | | 4013 |yes |256 KB |4.1.1 |  
 +^MacGyver  | P-m Dothan |1.7 GHz  | | 3400 |  yes | 2MB | 4.1.1 |  
 +^Infomob |Tri-Xeon  |2.80 GHz  | |5570  |yes  |512 KB  |3.2.2 
 +^Almighty  |PentiumD (DualCore64)  |3.4 GHz  | |6800  |yes  |2048 KB  |4.1.1 
 +^PC104  |Transmeta Crusoe TM5400  |500 MHz  | |997  |yes  |256 KB  |3.4.6 
 + 
 + 
 + 
 +==== /proc/cpuinfo ==== 
 + 
 + 
  
programming/instruction-timings.1166036320.txt.gz · Last modified: 2013/09/19 16:43 (external edit)
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