MySQL is faster than Redis. Am I missing something here? [closed]

Question

I've been considering using Redis in a project that uses a lot of writes.

So, after setting it up on my server, I created a simple PHP script using Predis with a simple loop to add records. I also created a second script that does a similar thing, only on a MySQL table (InnoDB) using PHP's MySQLi.

I ran a 10k loop, a 100k loop and a 500k loop and MySQL beat Redis every single time. In fact, the more records I added, the faster MySQL was compared to Redis.

There's so much buzz (hype?) around Redis, that I want to believe I'm missing something here.

Please educate me :)

Thanks!

Here's my Predis code:

for ($i=0; $i<100000; $i++) {
    $predis->set('key'.$i, $i);
}

Here's my MySQLi code:

for ($i=0; $i<100000; $i++) {
    mysqli_query($db, "INSERT INTO test (`key`, `value`) VALUES ('key$i', $i)");
}

Answer 1

Comparing predis to mysqli is inappropriate

the mysqli extension - is an extension whereas predis is a php-client library. I.e. whereas mysqli is compiled code, predis is just plain php - extensions are faster.

A benchmark of the kind shown in the question primarily shows the performance loss of PHP code versus an extension.

Compare like with like

If you want to make a comparison of write performance - you'll need to compare to the php redis extension.