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If we only consider execution times, the filtered databases have
similar results, though not presented here, as the sampled
databases. But since the constraint systems are of larger sizes, we
expect to have a different picture concerning the exceptions.
In fact,
6_tab:PerfectClub_satisfiability_64_32_exception_filter shows
that Simplex 64-bit has reduced from exceptions to
exceptions compared to its version 32-bit. The Double Description
method 32-bit raises overflow exceptions among which timeout
exceptions, i.e. , are expected using its 64-bit version.
Table 14:
PerfectClub: Numbers of exceptions in filtered database
|
PerfectClub |
timeout = 2 minutes |
#overflows |
#timeouts |
#operations |
JANUS 64-bit |
0 |
0 |
1310 |
JANUS 32-bit |
0 |
0 |
1310 |
Simplex 64-bit |
2 |
0 |
1310 |
Simplex 32-bit |
92 |
0 |
1310 |
Fourier-Motzkin 64-bit |
0 |
0 |
1310 |
Fourier-Motzkin 32-bit |
0 |
0 |
1310 |
Double Description 64-bit |
0 |
407 |
1310 |
Double Description 32-bit |
50 |
371 |
1310 |
|
6_tab:SPEC95_satisfiability_64_32_exception_filter shows
that using 32-bit instead of 64-bit results in many more overflow
exceptions. The Double Description method has the biggest difference:
to .
Table 15:
SPEC95: Numbers of exceptions in filtered database
|
SPEC95 |
timeout = 2 minutes |
#overflows |
#timeouts |
#operations |
JANUS 64-bit |
3050 |
0 |
4676 |
JANUS 32-bit |
3109 |
0 |
4676 |
Simplex 64-bit |
3174 |
0 |
4676 |
Simplex 32-bit |
3972 |
0 |
4676 |
Fourier-Motzkin 64-bit |
8 |
625 |
4676 |
Fourier-Motzkin 32-bit |
181 |
495 |
4676 |
Double Description 64-bit |
22 |
0 |
4676 |
Double Description 32-bit |
939 |
0 |
4676 |
|
Previous: 1. Sampled databases:
Up: 6. Arithmetic Precision: 64-bit
Next: 7. Conclusion
Nguyen Que Duong
2006-09-16