*** pg_test_timing.c.orig	2023-01-16 01:09:51.839251695 +0100
--- pg_test_timing.c	2023-01-16 22:24:49.768037225 +0100
***************
*** 11,16 ****
--- 11,20 ----
  #include "getopt_long.h"
  #include "portability/instr_time.h"
  
+ #define INSTR_TIME_GET_NANOSEC(t) \
+ 	(((uint64) (t).tv_sec * (uint64) 1000000000) + (uint64) ((t).tv_nsec))
+ 
+ 
  static const char *progname;
  
  static unsigned int test_duration = 3;
***************
*** 19,26 ****
  static uint64 test_timing(unsigned int duration);
  static void output(uint64 loop_count);
  
! /* record duration in powers of 2 microseconds */
! long long int histogram[32];
  
  int
  main(int argc, char *argv[])
--- 23,30 ----
  static uint64 test_timing(unsigned int duration);
  static void output(uint64 loop_count);
  
! /* record duration in powers of 2 nanoseconds */
! long long int histogram[64];
  
  int
  main(int argc, char *argv[])
***************
*** 124,139 ****
  	uint64		total_time;
  	int64		time_elapsed = 0;
  	uint64		loop_count = 0;
  	uint64		prev,
  				cur;
  	instr_time	start_time,
  				end_time,
  				temp;
  
! 	total_time = duration > 0 ? duration * INT64CONST(1000000) : 0;
  
  	INSTR_TIME_SET_CURRENT(start_time);
! 	cur = INSTR_TIME_GET_MICROSEC(start_time);
  
  	while (time_elapsed < total_time)
  	{
--- 128,145 ----
  	uint64		total_time;
  	int64		time_elapsed = 0;
  	uint64		loop_count = 0;
+ 	uint64		same_count = 0;
+ 	uint64		min_diff = UINT64_MAX;
  	uint64		prev,
  				cur;
  	instr_time	start_time,
  				end_time,
  				temp;
  
! 	total_time = duration > 0 ? duration * INT64CONST(1000000000) : 0;
  
  	INSTR_TIME_SET_CURRENT(start_time);
! 	cur = INSTR_TIME_GET_NANOSEC(start_time);
  
  	while (time_elapsed < total_time)
  	{
***************
*** 141,157 ****
  					bits = 0;
  
  		prev = cur;
  		INSTR_TIME_SET_CURRENT(temp);
! 		cur = INSTR_TIME_GET_MICROSEC(temp);
  		diff = cur - prev;
  
  		/* Did time go backwards? */
! 		if (diff < 0)
  		{
  			fprintf(stderr, _("Detected clock going backwards in time.\n"));
  			fprintf(stderr, _("Time warp: %d ms\n"), diff);
  			exit(1);
  		}
  
  		/* What is the highest bit in the time diff? */
  		while (diff)
--- 147,172 ----
  					bits = 0;
  
  		prev = cur;
+ //		INSTR_TIME_SET_CURRENT(temp);
+ //		prev = INSTR_TIME_GET_NANOSEC(temp);
  		INSTR_TIME_SET_CURRENT(temp);
! 		cur = INSTR_TIME_GET_NANOSEC(temp);
  		diff = cur - prev;
  
  		/* Did time go backwards? */
! 		if (unlikely(diff <= 0))
  		{
+ 			if (diff == 0 )
+ 				same_count ++;
+ 			else
+ 			{
  			fprintf(stderr, _("Detected clock going backwards in time.\n"));
  			fprintf(stderr, _("Time warp: %d ms\n"), diff);
  			exit(1);
+ 			}
  		}
+ 		if (min_diff > diff)
+ 			min_diff = diff;
  
  		/* What is the highest bit in the time diff? */
  		while (diff)
***************
*** 165,179 ****
  
  		loop_count++;
  		INSTR_TIME_SUBTRACT(temp, start_time);
! 		time_elapsed = INSTR_TIME_GET_MICROSEC(temp);
  	}
  
  	INSTR_TIME_SET_CURRENT(end_time);
  
  	INSTR_TIME_SUBTRACT(end_time, start_time);
  
! 	printf(_("Per loop time including overhead: %0.2f ns\n"),
! 		   INSTR_TIME_GET_DOUBLE(end_time) * 1e9 / loop_count);
  
  	return loop_count;
  }
--- 180,194 ----
  
  		loop_count++;
  		INSTR_TIME_SUBTRACT(temp, start_time);
! 		time_elapsed = INSTR_TIME_GET_NANOSEC(temp);
  	}
  
  	INSTR_TIME_SET_CURRENT(end_time);
  
  	INSTR_TIME_SUBTRACT(end_time, start_time);
  
! 	printf(_("Per loop time including overhead: %0.2f ns, min: %ld, same: %ld\n"),
! 		   INSTR_TIME_GET_DOUBLE(end_time) * 1e9 / loop_count, min_diff, same_count);
  
  	return loop_count;
  }
***************
*** 181,189 ****
  static void
  output(uint64 loop_count)
  {
! 	int64		max_bit = 31,
  				i;
! 	char	   *header1 = _("< us");
  	char	   *header2 = /* xgettext:no-c-format */ _("% of total");
  	char	   *header3 = _("count");
  	int			len1 = strlen(header1);
--- 196,204 ----
  static void
  output(uint64 loop_count)
  {
! 	int64		max_bit = 63,
  				i;
! 	char	   *header1 = _("< ns");
  	char	   *header2 = /* xgettext:no-c-format */ _("% of total");
  	char	   *header3 = _("count");
  	int			len1 = strlen(header1);
***************
*** 196,208 ****
  
  	printf(_("Histogram of timing durations:\n"));
  	printf("%*s   %*s %*s\n",
! 		   Max(6, len1), header1,
  		   Max(10, len2), header2,
  		   Max(10, len3), header3);
  
  	for (i = 0; i <= max_bit; i++)
  		printf("%*ld    %*.5f %*lld\n",
! 			   Max(6, len1), 1l << i,
  			   Max(10, len2) - 1, (double) histogram[i] * 100 / loop_count,
  			   Max(10, len3), histogram[i]);
  }
--- 211,223 ----
  
  	printf(_("Histogram of timing durations:\n"));
  	printf("%*s   %*s %*s\n",
! 		   Max(7, len1), header1,
  		   Max(10, len2), header2,
  		   Max(10, len3), header3);
  
  	for (i = 0; i <= max_bit; i++)
  		printf("%*ld    %*.5f %*lld\n",
! 			   Max(7, len1), 1l << i,
  			   Max(10, len2) - 1, (double) histogram[i] * 100 / loop_count,
  			   Max(10, len3), histogram[i]);
  }