use threads;
use threads::shared;
use strict;

use Time::HiRes qw/clock_gettime CLOCK_REALTIME usleep/;

my $flag:shared = 1;

print "starting at ".clock_gettime(CLOCK_REALTIME)."\n";

my @pool;
for(1..50){
	push @pool, threads->create(\&mysub);
}
print "giving the flag at ".clock_gettime(CLOCK_REALTIME)."\n";
$flag = 0; # all threads go!
$_->join for (@pool);
 
sub mysub {
    my $tid = threads->tid;
    while( $flag ){
	print "thread $tid created and waiting for the flag at ".clock_gettime(CLOCK_REALTIME)."\n";
	usleep(1000);
    }

    #my $x = 0.0001 + rand(0.0015);
    my $x = 0.001;
    #my $x = rand() >= 0.5 ? 0.001 : 1;
    print "thread $tid is working with sleep=$x, at ".clock_gettime(CLOCK_REALTIME)."\n";
    my $id;
    for my $i (1..100){
	$id = "i=$i, tid=$tid";
#	print `
	`
		echo -n "start($id/\$\$) on cpu "\`cat /proc/\$\$/stat | cut -d' ' -f39\`": "; date +%s.%N
		sleep $x
		echo -n " stop($id/\$\$) on cpu "\`cat /proc/\$\$/stat | cut -d' ' -f39\`": "; date +%s.%N
	`;
    }
    print "ended " . threads->tid . " at ".clock_gettime(CLOCK_REALTIME)."\n";
}
__END__