[Benchmark] PHP amqp-lib VS amqp-ext with Swarrot


Cause sometimes, performance matters.

The history

Everything start on 7 April 2014. We gave a talk with Grégoire Pineau (aka @lyrixx) called "Making asynchronous tasks in PHP" (slides are available on speakerdeck).

During this talk we trolled about the php-amqplib created by Alavaro Videla and maintained by a lot of users.

This library is one of the 2 main ways to talk to an amqp broker. The other one is the php extension.

Anyway, the subject has come back a few days ago on twitter (conversation is in French) when Ölbaum asked us if we still recommend to not use the php-amqplib. Some tweets later, I proposed to make a small benchmark to compare these 2 ways of talking to a broker. Because trolling is good but sometimes, having some real arguments is better.

Environment

  • The broker used is RabbitMQ (v3.3.5).
  • I launched tests on a Mac Book Pro (2,8 GHz Intel Core i7, 16 GB 1600 MHz DDR3 with OSX 10.10).
  • I used PHP 5.6.2.
  • I used the last stable version for both the extension (1.4.0) and the library (2.4.1).

I chose to use Swarrot to write as few code as possible for each implementation.

The full project used for this benchmark can be found on github. Of course, feel free to contribute and complete it!

Results

And now, the results. Every tests have been launched 3 times. What you see here is the average time of these 3 launches.

Publish 1 million messages in a direct exchange

Code is here The concerned queue has been purged before each launch.

./bench publish [ext|lib] -m 1000000

With the extension

+-------------+-------------+
| Duration    |  36 seconds |
+-------------+-------------+
| Memory peak | 1.5 MiB     |
+-------------+-------------+

With the library

+-------------+-------------+
| Duration    |  46 seconds |
+-------------+-------------+
| Memory peak | 2.5 MiB     |
+-------------+-------------+

So what?

The duration difference is pretty small between the extension and the library. In both case the memory consumption is very stable (I tried with 100, 1k, 10k, 100k messages, the memory consumption is near the same).

Get 100k messages from a queue (+ ack)

Code is here.

./bench get [ext|lib] -m 1000000

With the extension

+-------------+-------------+
| Duration    |  19 seconds |
+-------------+-------------+
| Memory peak | 1.8 MiB     |
+-------------+-------------+

With the library

+-------------+-------------+
| Duration    |  43 seconds |
+-------------+-------------+
| Memory peak | 2.8 MiB     |
+-------------+-------------+

So what?

For the memory consumption, again, nothing to say. It's low and stable in both case. To consume messages, the pecl extension is more than 2 times faster than the library.

Conclusion

The extension is faster than the library. C is faster than PHP. Is it really surprising? No! It's not really pertinent to compare 2 tools which obviously make the same job but have different implementations.

The main difference is the installation. The library is VERY simple to install! You just have to add "videlalvaro/php-amqplib": "~2.4" in your composer.json and you're done. On the contrary, for the extension, you generally need to compile the rabbitmq-c (an AMQP client in C used by the php extension) which can be a bit boring.

So, if you already install the extension and if it's not a problem for you, go for it! Otherwise, don't panic and use the library!

In both case, take a look at Swarrot (and the SwarrotBundle) to be able to change your choice if needed.

Tags: php, amqp, broker, swarrot