Shift of 5MB not really applied when setting a memory limit (#417)

* Creating a MemoryConsumptionChecker saying if the RAM is almost overloaded

* Using the MemoryConsumptionChecker to stop consuming messages when the RAM is almost overloaded

* Adding new line at the end of new files (for future coding review ease)

* Fixing the way to retrieve class name for backward compatibilities

Author: JonasHaouzi

MemoryChecker/MemoryConsumptionChecker.php

@@ -0,0 +1,65 @@
+<?php
+
+namespace OldSound\RabbitMqBundle\MemoryChecker;
+
+/**
+ * Help handling memory limits .
+ *
+ * @author Jonas Haouzi <jonas@viscaweb.com>
+ */
+class MemoryConsumptionChecker
+{
+    /** @var NativeMemoryUsageProvider */
+    private $memoryUsageProvider;
+
+    /**
+     * MemoryManager constructor.
+     *
+     * @param NativeMemoryUsageProvider $memoryUsageProvider
+     */
+    public function __construct(NativeMemoryUsageProvider $memoryUsageProvider) {
+        $this->memoryUsageProvider = $memoryUsageProvider;
+    }
+
+    /**
+     * @param int|string $allowedConsumptionUntil
+     * @param int|string $maxConsumptionAllowed
+     *
+     * @return bool
+     */
+    public function isRamAlmostOverloaded($allowedConsumptionUntil, $maxConsumptionAllowed)
+    {
+        $allowedConsumptionUntil = $this->convertHumanUnitToNumerical($allowedConsumptionUntil);
+        $maxConsumptionAllowed = $this->convertHumanUnitToNumerical($maxConsumptionAllowed);
+        $currentUsage = $this->convertHumanUnitToNumerical($this->memoryUsageProvider->getMemoryUsage());
+
+        return $currentUsage > ($maxConsumptionAllowed - $allowedConsumptionUntil);
+    }
+
+    /**
+     * @param int|string $humanUnit
+     *
+     * @return int
+     */
+    private function convertHumanUnitToNumerical($humanUnit)
+    {
+        $numerical = $humanUnit;
+        if (!is_numeric($humanUnit)) {
+            $numerical = substr($numerical, 0, -1);
+            switch (substr($humanUnit, -1)) {
+                case 'G':
+                    $numerical *= pow(1024, 3);
+                    break;
+                case 'M':
+                    $numerical *= pow(1024, 2);
+                    break;
+                case 'K':
+                    $numerical *= 1024;
+                    break;
+            }
+        }
+
+        return (int)$numerical;
+    }
+
+}

MemoryChecker/NativeMemoryUsageProvider.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace OldSound\RabbitMqBundle\MemoryChecker;
+
+/**
+ * Returns the current memory PHP is using (mainly used to allow mocking).
+ *
+ * @author Jonas Haouzi <jonas@viscaweb.com>
+ */
+class NativeMemoryUsageProvider
+{
+    /**
+     * @return int
+     */
+    public function getMemoryUsage()
+    {
+        return memory_get_usage(true);
+    }
+}

RabbitMq/Consumer.php

@@ -5,6 +5,8 @@
 use OldSound\RabbitMqBundle\Event\AfterProcessingMessageEvent;
 use OldSound\RabbitMqBundle\Event\BeforeProcessingMessageEvent;
 use OldSound\RabbitMqBundle\Event\OnConsumeEvent;
+use OldSound\RabbitMqBundle\MemoryChecker\MemoryConsumptionChecker;
+use OldSound\RabbitMqBundle\MemoryChecker\NativeMemoryUsageProvider;
 use PhpAmqpLib\Exception\AMQPTimeoutException;
 use PhpAmqpLib\Message\AMQPMessage;
 
@@ -164,10 +166,8 @@ protected function handleProcessMessage(AMQPMessage $msg, $processFlag)
      */
     protected function isRamAlmostOverloaded()
     {
-        if (memory_get_usage(true) >= ($this->getMemoryLimit() * 1024 * 1024)) {
-            return true;
-        } else {
-            return false;
-        }
+        $memoryManager = new MemoryConsumptionChecker(new NativeMemoryUsageProvider());
+
+        return $memoryManager->isRamAlmostOverloaded($this->getMemoryLimit(), '5M');
     }
 }

Tests/Manager/MemoryCheckerTest.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace OldSound\RabbitMqBundle\Tests\Event;
+
+use OldSound\RabbitMqBundle\MemoryChecker\MemoryConsumptionChecker;
+use OldSound\RabbitMqBundle\MemoryChecker\NativeMemoryUsageProvider;
+
+/**
+ * Class MemoryManagerTest
+ *
+ * @package OldSound\RabbitMqBundle\Tests\Manager
+ */
+class MemoryConsumptionCheckerTest extends \PHPUnit_Framework_TestCase
+{
+    public function testMemoryIsNotAlmostOverloaded()
+    {
+        $currentMemoryUsage = '7M';
+        $allowedConsumptionUntil = '2M';
+        $maxConsumptionAllowed = '10M';
+
+        $memoryUsageProvider = $this->getMockBuilder('OldSound\\RabbitMqBundle\\MemoryChecker\\NativeMemoryUsageProvider')->getMock();
+        $memoryUsageProvider->expects($this->any())->method('getMemoryUsage')->willReturn($currentMemoryUsage);
+
+        $memoryManager = new MemoryConsumptionChecker($memoryUsageProvider);
+
+        $this->assertFalse($memoryManager->isRamAlmostOverloaded($allowedConsumptionUntil, $maxConsumptionAllowed));
+    }
+
+    public function testMemoryIsAlmostOverloaded()
+    {
+        $currentMemoryUsage = '9M';
+        $allowedConsumptionUntil = '2M';
+        $maxConsumptionAllowed = '10M';
+
+        $memoryUsageProvider = $this->getMockBuilder('OldSound\\RabbitMqBundle\\MemoryChecker\\NativeMemoryUsageProvider')->getMock();
+        $memoryUsageProvider->expects($this->any())->method('getMemoryUsage')->willReturn($currentMemoryUsage);
+
+        $memoryManager = new MemoryConsumptionChecker($memoryUsageProvider);
+
+        $this->assertTrue($memoryManager->isRamAlmostOverloaded($allowedConsumptionUntil, $maxConsumptionAllowed));
+    }
+}