[BUG]: Phalcon\Support classes leak memory

[maxgalbu]

Describe the bug
Instantiating and invoking a Phalcon/Support class make memory grow too much.
I'm using it in a forever-running CLI script.

To Reproduce

Script to reproduce the behavior:

<?php
use Phalcon\Support\HelperFactory;

echo "beginning: ".memory_get_peak_usage() / 1024 / 1024;
echo "\n";

foreach (range(1,100000) as $num) {
    $helper = new HelperFactory();
    $helper->camelize("transaction_id");
}

echo "end: ".memory_get_peak_usage() / 1024 / 1024;
echo "\n";

Output:

beginning: 0.40937042236328
end: 42.013931274414

Expected behavior
Memory should not increase so much. Same output using ucwords():

beginning: 0.40864562988281
end: 4.3784713745117

Details

• Phalcon version: 5.6.2
• PHP Version: 8.1.27
• Operating System: Debian
• Installation type: installing via package manager
• Zephir version (if any):
• Server: N/A (cli script)

[niden]

That should be normal to be honest.

The helper factory is just that, a factory that creates additional classes. When you instantiate the factory, you have one object. Once you call say camelize on it, it will create the Camelize object transparently (and the memory will increase by doing that) and then use it to produce the result. Any subsequent calls to camelize will not increase the memory since it is already instantiated.

[niden]

Actually I take that back. That is what should be happening but it is not. The mapper is not reusing the object.

I will sort that out shortly

[niden]

I run the same test with some variations.

In the test you have, you are creating the helper factory and then calling camelize which in turn will create a new Camelize object. This is in the loop so you are pretty much testing what is the memory consumption of two objects being created in a loop, again and again, so this does not represent a memory leak. The better tests are as follows (to see if there is a memory leak or not)

• Create the factory outside the loop, run the loop with the camelize in it, and see if the memory keeps increasing
• Create the factory and call camelize outside the loop, then call camelize in the loop.

After the change I made (PR will be coming shortly) I got these results

Your test as is:

beginning: 0.41312408447266
end: 35.912994384766

Create factory outside the loop

beginning: 0.41301727294922
end: 35.903160095215

Create the factory outside the loop and call camelize, then have camelize in the loop

beginning: 0.41147613525391
end: 35.903717041016

[niden]

#16574

Resolved

[maxgalbu]

In the test you have, you are creating the helper factory and then calling camelize which in turn will create a new Camelize object. This is in the loop so you are pretty much testing what is the memory consumption of two objects being created in a loop, again and again, so this does not represent a memory leak.

I'm creating the helper factory but I'm also storing every instance on the same variable $helper. Shouldn't this call the destructor on the old Factory instance every time I instantiate another Factory? Why is the old instance kept in memory?

With the following userland code mimicking HelperFactory from phalcon, the memory increases linearly just like using ucwords:

<?php

echo "beginning: ".memory_get_peak_usage() / 1024 / 1024;
echo "\n";

class Camelize
{
    public function __invoke(
        string $text,
        string $delimiters = null,
        bool $lowerFirst = false
    ): string {
        if (!$delimiters) {
            $delimiters = "\n\t";
        }
        return str_replace(str_split($delimiters), "", ucwords($text, $delimiters));
    }
}

class HelperFactory
{
    private array $services = [];

    public function __call(string $name, array $arguments)
    {
        $helper = $this->newInstance($name);
        return call_user_func_array([$helper, "__invoke"], $arguments);
    }

    public function newInstance(string $name)
    {
        if (!isset($this->services[$name])) {
            $instanceName = $this->getService($name);
            $this->services[$name] = new $instanceName;
        }

        return $this->services[$name];
    }

    protected function getService($name)
    {
        return [
            "camelize"      => "Camelize",
        ][$name];
    }
}

foreach (range(1,100000) as $num) {
    $helper = new HelperFactory();
    $helper->camelize("transaction_id");
}

echo "end: ".memory_get_peak_usage() / 1024 / 1024;
echo "\n";

Output:

beginning: 0.41677856445312
end: 4.3862762451172

After the change I made (PR will be coming shortly) I got these results

Looking at these results, there seems to be no improvements at all? At least with Create factory outside the loop there should be some improvements..

[maxgalbu]

@niden did you look at my comment? maybe you just mis-copied results after your fix?