Benchmark memcached vs memcache vs redis

My setup:
Fedora 25,Nginx 1.10.2,redis 3.1.2,memcache 3.0.9,memcached 3.0.3,php-fpm 7.0.17.

My Benchmark script(php)

<?php
################# memcached ###################################################
    
    $k=0;
    $t_time=0;
    echo "
Benchmark memcached : 
";
    $memcached = new Memcached;  
    $memcached->addServer("127.0.0.1", 11211)or die ("Cannot connect");  

    $original_string = 'abcdefghijklmnopqrstuvwxyz';    
    for ($i=0;$i<=10000;$i++){
        $random_string = get_random_string($original_string, 10);
        $random_string2 = get_random_string($original_string, 10);
        $a1[$i]=$random_string;
        $a2[$random_string]=$random_string2;
    }    
    $tstart=timer_start();        
    for ($i=0;$i<=10000;$i++){                
        $memcached->set($a1[$i], $a2[$a1[$i]],20) or die ("Cannot save data");
    }
    $t_time=timer_end($tstart);    
    echo "Total Set time: ".$t_time."
";        
    for ($j=0;$j<10;$j++){    
        $tstart=timer_start();    
        for ($i=0;$i<=10000;$i++){            
            $value = $memcached->get($a1[$i]);              
        }    
        $t_time=timer_end($tstart);
        echo "Loop $j (Get) time: ".$t_time."
";        
        $k=$k+$t_time;    
    } 
    echo "Total 10 loop Get time $k 
";    

################# memcache ###################################################

    $k=0;
    $t_time=0;
    echo "
Benchmark memcache : 
";
    $memcache = new Memcache;  
    $memcache->connect('127.0.0.1', 11211) or die ("Cannot connect");  

    $original_string = 'abcdefghijklmnopqrstuvwxyz';    
    for ($i=0;$i<=10000;$i++){
        $random_string = get_random_string($original_string, 10);
        $random_string2 = get_random_string($original_string, 10);
        $a1[$i]=$random_string;
        $a2[$random_string]=$random_string2;
    }    
    $tstart=timer_start();        
    for ($i=0;$i<=10000;$i++){        
        $memcache->set($a1[$i], $a2[$a1[$i]], false, 20) or die ("Cannot save data");
    }
    $t_time=timer_end($tstart);    
    echo "Total Set time: ".$t_time."
";        
    for ($j=0;$j<10;$j++){    
        $tstart=timer_start();    
        for ($i=0;$i<=10000;$i++){            
            $value = $memcache->get($a1[$i]);              
        }    
        $t_time=timer_end($tstart);
        echo "Loop $j (Get) time: ".$t_time."
";        
        $k=$k+$t_time;    
    } 
    echo "Total 10 loop Get time $k 
";

################# redis ###################################################

    $k=0;
    $t_time=0;
    echo "
Benchmark redis : 
";
    $redis = new Redis();
    $redis->connect('127.0.0.1', 6379);
    
    $original_string = 'abcdefghijklmnopqrstuvwxyz';    
    for ($i=0;$i<=10000;$i++){
        $random_string = get_random_string($original_string, 10);
        $random_string2 = get_random_string($original_string, 10);
        $a1[$i]=$random_string;
        $a2[$random_string]=$random_string2;
    }    
    $tstart=timer_start();    
    for ($i=0;$i<=10000;$i++){
        $redis -> set($a1[$i],$a2[$a1[$i]]);        
    }
    $t_time=timer_end($tstart);    
    echo "Total Set time: ".$t_time."
";    
    for ($j=0;$j<10;$j++){
        $tstart=timer_start();        
        for ($i=0;$i<=10000;$i++){            
            $value=$redis -> get($a1[$i]);            
        }
    $t_time=timer_end($tstart);        
    echo "Loop $j (Get) time: ".$t_time."
";
    $k=$k+$t_time;    
    }     
    echo "Total 10 loop Get time $k 
";

   

function timer_start()   
{   $time = microtime();
    $time = explode(" ", $time);
    $time = $time[1] + $time[0];
    return $time;    
}   
function timer_end($start)
{   $time = microtime();
    $time = explode(" ", $time);
    $time = $time[1] + $time[0];    
    return $time-$start;    
}
   
function get_random_string($valid_chars, $length)
{   
    // start with an empty random string
    $random_string = "";

    // count the number of chars in the valid chars string so we know how many choices we have
    $num_valid_chars = strlen($valid_chars);

    // repeat the steps until we've created a string of the right length
    for ($i = 0; $i < $length; $i++)
    {
        // pick a random number from 1 up to the number of valid chars
        $random_pick = mt_rand(1, $num_valid_chars);

        // take the random character out of the string of valid chars
        // subtract 1 from $random_pick because strings are indexed starting at 0, and we started picking at 1
        $random_char = $valid_chars[$random_pick-1];

        // add the randomly-chosen char onto the end of our string so far
        $random_string .= $random_char;
    }

    // return our finished random string
    return $random_string;
} 
?>

Benchmark memcached : 
Total Set time: 0.69209885597229
Loop 0 (Get) time: 0.68401622772217
Loop 1 (Get) time: 0.67029213905334
Loop 2 (Get) time: 0.77216291427612
Loop 3 (Get) time: 0.68823003768921
Loop 4 (Get) time: 0.68713402748108
Loop 5 (Get) time: 0.66251420974731
Loop 6 (Get) time: 0.66882991790771
Loop 7 (Get) time: 0.63542795181274
Loop 8 (Get) time: 0.66616487503052
Loop 9 (Get) time: 0.66425609588623
Total 10 loop Get time 6.7990283966064 

Benchmark memcache : 
Total Set time: 0.72946310043335
Loop 0 (Get) time: 0.55730509757996
Loop 1 (Get) time: 0.46489191055298
Loop 2 (Get) time: 0.68988108634949
Loop 3 (Get) time: 0.73450708389282
Loop 4 (Get) time: 0.68325591087341
Loop 5 (Get) time: 0.67392992973328
Loop 6 (Get) time: 0.7195930480957
Loop 7 (Get) time: 0.74770784378052
Loop 8 (Get) time: 0.70041298866272
Loop 9 (Get) time: 0.70169019699097
Total 10 loop Get time 6.6731750965118 

Benchmark redis : 
Total Set time: 0.69859886169434
Loop 0 (Get) time: 0.69667816162109
Loop 1 (Get) time: 0.65093517303467
Loop 2 (Get) time: 0.68474006652832
Loop 3 (Get) time: 0.7402458190918
Loop 4 (Get) time: 0.6503758430481
Loop 5 (Get) time: 0.66205310821533
Loop 6 (Get) time: 0.70370101928711
Loop 7 (Get) time: 0.646409034729
Loop 8 (Get) time: 0.66896295547485
Loop 9 (Get) time: 0.67996406555176
Total 10 loop Get time 6.784065246582 

The results shows for simple Set and Get,memcached is quite comparable to redis.
And the result is not repeatable. Different results occurrs at different run.

For other functions,more extensive tests/benchmarks have to perform on both.