diff --git a/pipepar/test_gomp.c b/pipepar/test_gomp.c
new file mode 100644
index 0000000..0bc7ea1
--- /dev/null
+++ b/pipepar/test_gomp.c
@@ -0,0 +1,167 @@
+#include <sys/time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <errno.h>
+
+
+#define TIMEINF(t1, t2) ((t1.tv_sec < t2.tv_sec) || (t1.tv_usec < t2.tv_usec))
+#define STRTOL_OVERFLOW(n) (((n == LONG_MIN) || (n == LONG_MAX)) && \
+			    (errno == ERANGE))
+
+long busy_usecs = 42;
+long total_time_usecs = 42;
+unsigned int seed;
+
+void node(long entry_input, long *entry_output)
+{
+	//struct timeval cur_time, end_time;
+	//long long usecs;
+	long entry;
+	static long inc = 0;
+
+	entry = entry_input + inc++;
+	/*gettimeofday(&cur_time, 0);
+	usecs = busy_usecs + cur_time.tv_usec + cur_time.tv_sec * 1000000;
+	end_time.tv_usec = usecs % 1000000;
+	end_time.tv_sec = usecs / 1000000;
+	while (TIMEINF(cur_time, end_time))
+		gettimeofday(&cur_time, 0);*/
+	*entry_output = entry;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j, seed;
+	char **arg_p;
+	long entries_1[8], entries_2[8], entries_3[8], entries_4[8], entries_5[8], entries_6[8];
+	//long entries_7[8], entries_8[8], entries_9[8], entries_10[8];
+	long entries_input[8], entries_output[8];
+	long nb_entries, result;
+
+	argc--;
+	arg_p = argv;
+	while(arg_p++, argc--)
+	{
+		if ((*arg_p)[0] == '-')
+		{
+			if ((!(*arg_p)[1]) || (*arg_p)[2])
+			{
+				printf("Unsupported option: %s\n", *arg_p);
+				return -1;
+			}
+			switch((*arg_p)[1])
+			{
+				char *endptr;
+
+				case 't':
+					argc--, arg_p++;
+					busy_usecs = strtol(*arg_p, &endptr,
+							       10);
+					if ((endptr == *arg_p) ||
+					    (STRTOL_OVERFLOW(busy_usecs)))
+					{
+						fprintf(stderr, "Invalid time: "
+								"%s\n", *arg_p);
+						return -1;
+					}
+					break;
+
+				case 'T':
+					argc--, arg_p++;
+					total_time_usecs = strtol(*arg_p,
+								  &endptr, 10);
+					if ((endptr == *arg_p) ||
+					    (STRTOL_OVERFLOW(total_time_usecs)))
+					{
+						fprintf(stderr, "Invalid time: "
+								"%s\n", *arg_p);
+						return -1;
+					}
+					break;
+
+				default:
+					printf("Unsupported option: %s\n", *arg_p);
+					return -1;
+			}
+		}
+	}
+
+	nb_entries = total_time_usecs / busy_usecs;
+	printf("total_time_usecs: %ld, busy_usecs: %ld, nb_entries: %ld\n", total_time_usecs, busy_usecs, nb_entries);
+	seed = 42;
+	result = 0;
+
+#pragma omp parallel num_threads (1) default (none) \
+	shared (nb_entries, entries_output, seed, result) \
+	private (entries_input, entries_1, entries_2, entries_3, entries_4, entries_5, entries_6, i, j)
+	//private (entries_input, entries_1, entries_2, entries_3, entries_4, entries_5, entries_6, entries_7, entries_8, entries_9, entries_10, i, j)
+	{
+#pragma omp single
+		{
+			long random = rand_r(&seed);
+			long inc;
+
+			inc = random;
+			for (i = 0; i < nb_entries; i += 64 / sizeof(long))
+			{
+
+#pragma omp task output (entries_input) shared (inc) private (j)
+				{
+					for (j = 0; j < 64 / sizeof(long); j++)
+						entries_input[j] = inc++;
+				}
+#pragma omp task input (entries_input) output (entries_1) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_input[j], &entries_1[j]);
+
+
+#pragma omp task input (entries_1) output (entries_2) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_1[j], &entries_2[j]);
+#pragma omp task input (entries_2) output (entries_3) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_2[j], &entries_3[j]);
+
+
+#pragma omp task input (entries_3) output (entries_4) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_3[j], &entries_4[j]);
+#pragma omp task input (entries_4) output (entries_5) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_4[j], &entries_5[j]);
+
+
+#pragma omp task input (entries_5) output (entries_6) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_5[j], &entries_6[j]);
+#if 0
+#pragma omp task input (entries_6) output (entries_7) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_6[j], &entries_7[j]);
+
+
+#pragma omp task input (entries_7) output (entries_8) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_7[j], &entries_8[j]);
+#pragma omp task input (entries_8) output (entries_9) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_8[j], &entries_9[j]);
+
+
+#pragma omp task input (entries_9) output (entries_10) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+					node(entries_9[j], &entries_10[j]);
+#endif
+#pragma omp task input (entries_6) shared (result, entries_output) private (j)
+				for (j = 0; j < 64 / sizeof(long); j++)
+				{
+					node(entries_6[j], &entries_output[j]);
+					result += entries_output[j];
+				}
+			}
+		}
+	}
+	printf("result: %ld\n", result);
+	return 0;
+}