Don't sleep FOR one second, sleep until the NEXT second. 

#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11111868
use warnings;
use Time::HiRes qw( time sleep );

while(1)
  {
  my $nextsecond = int time + 1;
  sleep $nextsecond - time;
  print time, "\n";
  }

[download]

Outputs: 

1579965143.0001
1579965144.00009
1579965145.00009
1579965146.00009
1579965147.0001
1579965148.0001
1579965149.00009
1579965150.0001
1579965151.0001
1579965152.00009
1579965153.00009
1579965154.0001
1579965155.00009
1579965156.00009
1579965157.00009
...

[download]

In reply to Re: missing second of time by tybalt89
in thread missing second of time by Anonymous Monk

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