//! Test that two tick_count values recorded on different threads can be meaningfully subtracted.
void TestTickCountDifference( int n ) {
const double tolerance = 3E-4;
tick_count_array = new tbb::tick_count[n];
int num_trials = 0;
tbb::tick_count start_time = tbb::tick_count::now();
do {
NativeParallelFor( n, TickCountDifferenceBody( n ) );
if ( barrier_time > tolerance )
// The machine seems to be oversubscibed so skip the test.
continue;
for ( int i = 0; i < n; ++i ) {
for ( int j = 0; j < i; ++j ) {
double diff = (tick_count_array[i] - tick_count_array[j]).seconds();
if ( diff < 0 ) diff = -diff;
if ( diff > tolerance )
REPORT( "Warning: cross-thread tick_count difference = %g > %g = tolerance\n", diff, tolerance );
ASSERT( diff < 3 * tolerance, "Too big difference." );
}
}
// During 5 seconds we are trying to get 10 successful trials.
} while ( ++num_trials < 10 && (tbb::tick_count::now() - start_time).seconds() < 5 );
REMARK( "Difference test time: %g sec\n", (tbb::tick_count::now() - start_time).seconds() );
ASSERT( num_trials == 10, "The machine seems to be heavily oversubscibed, difference test was skipped." );
delete[] tick_count_array;
}
//! Test that two tick_count values recorded on different threads can be meaningfully subtracted.
void TestTickCountDifference( int n ) {
double tolerance = 3E-4;
for( int trial=0; trial<10; ++trial ) {
Counter = n;
Flag = false;
NativeParallelFor( n, TickCountDifferenceBody() );
ASSERT( Counter==0, NULL );
for( int i=0; i<n; ++i )
for( int j=0; j<i; ++j ) {
double diff = (tick_count_array[i]-tick_count_array[j]).seconds();
if( diff<0 ) diff = -diff;
if( diff>tolerance ) {
REPORT("%s: cross-thread tick_count difference = %g > %g = tolerance\n",
diff>3*tolerance?"ERROR":"Warning",diff,tolerance);
}
}
}
}
