MYSQLND MYSQLI_ASYNC pretty much useless for single connection

gistfile1.php

############################################################
###
###      Useless for a single mysql connection trying to
###      ASYNC multiple db calls
###

$link1 = mysqli_connect("localhost","user","pwd","dbname");

$s1 = "SELECT SLEEP(10)";
$s2 = "SELECT SLEEP(5)";
$s3 = "Select SLEEP(0)";
mysqli_query($link1, $s1, MYSQLI_ASYNC);
mysqli_query($link1, $s2, MYSQLI_ASYNC);
mysqli_query($link1, $s3, MYSQLI_ASYNC);


$started=time();
for ($x=0; $x<5; $x++) 
{
    $ready = $reject = $errors = array($link1, $link1, $link1);
    print "\niteration $x at t+" . (time()-$started) . "\n";
    mysqli_poll($ready, $errors, $reject, 1);
    print "ready = " . count($ready) . "\n";
    foreach($ready as $r) {
       $result = mysqli_reap_async_query($r);
       if(is_object($result))
       {
            print_r($result->fetch_array(MYSQLI_ASSOC));
            mysqli_free_result($result);
        }
    };
    sleep(4);
 }


## Will output:

    iteration 0 at t+0
    ready = 0

    iteration 1 at t+5
    ready = 0
    
    iteration 2 at t+10
    ready = 3
    Array
    (
        [SLEEP(10)] => 0
    )
    
    iteration 3 at t+14
    ready = 0
    
    iteration 4 at t+19
    ready = 0



############################################################
###
###      Works for multiple mysql connections
###

$link1 = mysqli_connect("localhost","user","pwd","dbname");
$link2 = mysqli_connect("localhost","user","pwd","dbname");
$link3 = mysqli_connect("localhost","user","pwd","dbname");

$s1 = "SELECT SLEEP(10)";
$s2 = "SELECT SLEEP(5)";
$s3 = "Select SLEEP(0)";
mysqli_query($link1, $s1, MYSQLI_ASYNC);
mysqli_query($link2, $s2, MYSQLI_ASYNC);
mysqli_query($link3, $s3, MYSQLI_ASYNC);


$started=time();
for ($x=0; $x<5; $x++) 
{
    $ready = $reject = $errors = array($link1, $link2, $link3);
    print "\niteration $x at t+" . (time()-$started) . "\n";
    mysqli_poll($ready, $errors, $reject, 1);
    print "ready = " . count($ready) . "\n";
    foreach($ready as $r) {
       $result = mysqli_reap_async_query($r);
       if(is_object($result))
       {
            print_r($result->fetch_array(MYSQLI_ASSOC));
            mysqli_free_result($result);
        }
    };
    sleep(4);
 }


## will output

    iteration 0 at t+0
    ready = 1
    Array
    (
        [SLEEP(0)] => 0
    )
    
    iteration 1 at t+4
    ready = 1
    Array
    (
        [SLEEP(5)] => 0
    )
    
    iteration 2 at t+9
    ready = 1
    Array
    (
        [SLEEP(10)] => 0
    )
    
    iteration 3 at t+14
    ready = 0
    
    iteration 4 at t+19
    ready = 0