pd.if.org Git - liblfds/blob - liblfds/liblfds6.0.1/test/src/benchmark_ringbuffer.c

   1 #include "internal.h"
   2
   3
   4
   5
   6
   7 /****************************************************************************/
   8 void benchmark_lfds601_ringbuffer( void )
   9 {
  10   unsigned int
  11     loop,
  12     thread_count,
  13     cpu_count;
  14
  15   struct lfds601_ringbuffer_state
  16     *rs;
  17
  18   struct lfds601_ringbuffer_benchmark
  19     *rb;
  20
  21   thread_state_t
  22     *thread_handles;
  23
  24   lfds601_atom_t
  25     total_operations_for_full_test_for_all_cpus,
  26     total_operations_for_full_test_for_all_cpus_for_one_cpu = 0;
  27
  28   double
  29     mean_operations_per_second_per_cpu,
  30     difference_per_second_per_cpu,
  31     total_difference_per_second_per_cpu,
  32     std_dev_per_second_per_cpu,
  33     scalability;
  34
  35   /* TRD : here we benchmark the ringbuffer
  36
  37            the benchmark is to have a single ringbuffer
  38            where a worker thread busy-works writing and then reading
  39   */
  40
  41   cpu_count = abstraction_cpu_count();
  42
  43   thread_handles = (thread_state_t *) malloc( sizeof(thread_state_t) * cpu_count );
  44
  45   rb = (struct lfds601_ringbuffer_benchmark *) malloc( sizeof(struct lfds601_ringbuffer_benchmark) * cpu_count );
  46
  47   // TRD : print the benchmark ID and CSV header
  48   printf( "\n"
  49           "Release %s Ringbuffer Benchmark #1\n"
  50           "CPUs,total ops,mean ops/sec per CPU,standard deviation,scalability\n", LFDS601_RELEASE_NUMBER_STRING );
  51
  52   // TRD : we run CPU count times for scalability
  53   for( thread_count = 1 ; thread_count <= cpu_count ; thread_count++ )
  54   {
  55     // TRD : initialisation
  56     lfds601_ringbuffer_new( &rs, 1000, NULL, NULL );
  57
  58     for( loop = 0 ; loop < cpu_count ; loop++ )
  59     {
  60       (rb+loop)->rs = rs;
  61       (rb+loop)->operation_count = 0;
  62     }
  63
  64     // TRD : main test
  65     for( loop = 0 ; loop < thread_count ; loop++ )
  66       abstraction_thread_start( &thread_handles[loop], loop, benchmark_lfds601_ringbuffer_thread_write_and_read, rb+loop );
  67
  68     for( loop = 0 ; loop < thread_count ; loop++ )
  69       abstraction_thread_wait( thread_handles[loop] );
  70
  71     // TRD : post test math
  72     total_operations_for_full_test_for_all_cpus = 0;
  73     total_difference_per_second_per_cpu = 0;
  74
  75     for( loop = 0 ; loop < thread_count ; loop++ )
  76       total_operations_for_full_test_for_all_cpus += (rb+loop)->operation_count;
  77
  78     mean_operations_per_second_per_cpu = ((double) total_operations_for_full_test_for_all_cpus / (double) thread_count) / (double) 10;
  79
  80     if( thread_count == 1 )
  81       total_operations_for_full_test_for_all_cpus_for_one_cpu = total_operations_for_full_test_for_all_cpus;
  82
  83     for( loop = 0 ; loop < thread_count ; loop++ )
  84     {
  85       difference_per_second_per_cpu = ((double) (rb+loop)->operation_count / (double) 10) - mean_operations_per_second_per_cpu;
  86       total_difference_per_second_per_cpu += difference_per_second_per_cpu * difference_per_second_per_cpu;
  87     }
  88
  89     std_dev_per_second_per_cpu = sqrt( (double) total_difference_per_second_per_cpu );
  90
  91     scalability = (double) total_operations_for_full_test_for_all_cpus / (double) (total_operations_for_full_test_for_all_cpus_for_one_cpu * thread_count);
  92
  93     printf( "%u,%u,%.0f,%.0f,%0.2f\n", thread_count, (unsigned int) total_operations_for_full_test_for_all_cpus, mean_operations_per_second_per_cpu, std_dev_per_second_per_cpu, scalability );
  94
  95     // TRD : cleanup
  96     lfds601_ringbuffer_delete( rs, NULL, NULL );
  97   }
  98
  99   free( rb );
 100
 101   free( thread_handles );
 102
 103   return;
 104 }
 105
 106
 107
 108
 109
 110 /****************************************************************************/
 111 thread_return_t CALLING_CONVENTION benchmark_lfds601_ringbuffer_thread_write_and_read( void *lfds601_ringbuffer_benchmark )
 112 {
 113   struct lfds601_ringbuffer_benchmark
 114     *rb;
 115
 116   struct lfds601_freelist_element
 117     *fe;
 118
 119   time_t
 120     start_time;
 121
 122   assert( lfds601_ringbuffer_benchmark != NULL );
 123
 124   rb = (struct lfds601_ringbuffer_benchmark *) lfds601_ringbuffer_benchmark;
 125
 126   time( &start_time );
 127
 128   while( time(NULL) < start_time + 10 )
 129   {
 130     lfds601_ringbuffer_get_write_element( rb->rs, &fe, NULL );
 131     lfds601_ringbuffer_put_write_element( rb->rs, fe );
 132
 133     lfds601_ringbuffer_get_read_element( rb->rs, &fe );
 134     lfds601_ringbuffer_put_read_element( rb->rs, fe );
 135
 136     rb->operation_count += 2;
 137   }
 138
 139   return( (thread_return_t) EXIT_SUCCESS );
 140 }
 141