diff --git a/library/Icinga/File/Pdf.php b/library/Icinga/File/Pdf.php
index 242e2ddd8..dfe8f74d3 100644
--- a/library/Icinga/File/Pdf.php
+++ b/library/Icinga/File/Pdf.php
@@ -8,6 +8,7 @@ use Dompdf\Dompdf;
 use Dompdf\Options;
 use Icinga\Application\Icinga;
 use Icinga\Exception\ProgrammingError;
+use Icinga\Util\Environment;
 use Icinga\Web\Hook;
 use Icinga\Web\Url;
 
@@ -45,8 +46,10 @@ class Pdf
     public function renderControllerAction($controller)
     {
         $this->assertNoHeadersSent();
-        ini_set('memory_limit', '384M');
-        ini_set('max_execution_time', 300);
+
+        Environment::raiseMemoryLimit('512M');
+        Environment::raiseExecutionTime(300);
+
         $viewRenderer = $controller->getHelper('viewRenderer');
         $controller->render(
             $viewRenderer->getScriptAction(),
diff --git a/library/Icinga/Util/Environment.php b/library/Icinga/Util/Environment.php
new file mode 100644
index 000000000..8d47b84d5
--- /dev/null
+++ b/library/Icinga/Util/Environment.php
@@ -0,0 +1,42 @@
+<?php
+/* Icinga Web 2 | (c) 2018 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Util;
+
+/**
+ * Helper for configuring the PHP environment
+ */
+class Environment
+{
+    /**
+     * Raise the PHP memory_limit
+     *
+     * Unless it is not already set to a higher limit
+     *
+     * @param string|int $minimum
+     */
+    public static function raiseMemoryLimit($minimum = '512M')
+    {
+        if (is_string($minimum)) {
+            $minimum = Format::unpackShorthandBytes($minimum);
+        }
+
+        if (Format::unpackShorthandBytes(ini_get('memory_limit')) < $minimum) {
+            ini_set('memory_limit', $minimum);
+        }
+    }
+
+    /**
+     * Raise the PHP max_execution_time
+     *
+     * Unless it is not already configured to a higher value.
+     *
+     * @param int $minimum
+     */
+    public static function raiseExecutionTime($minimum = 300)
+    {
+        if ((int) ini_get('max_execution_time') < $minimum) {
+            ini_set('max_execution_time', $minimum);
+        }
+    }
+}
diff --git a/library/Icinga/Util/Format.php b/library/Icinga/Util/Format.php
index b43be49cc..f3e682128 100644
--- a/library/Icinga/Util/Format.php
+++ b/library/Icinga/Util/Format.php
@@ -4,8 +4,6 @@
 namespace Icinga\Util;
 
 use DateTime;
-use Icinga\Date\DateFormatter;
-use Icinga\Exception\ProgrammingError;
 
 class Format
 {
@@ -141,4 +139,37 @@ class Format
 
         return $dt->format('L') == 1;
     }
+
+    /**
+     * Unpack shorthand bytes PHP directives to bytes
+     *
+     * @param   string  $subject
+     *
+     * @return  int
+     */
+    public static function unpackShorthandBytes($subject)
+    {
+        $base = (int) $subject;
+
+        if ($base <= -1) {
+            return INF;
+        }
+
+        switch (strtoupper($subject[strlen($subject) - 1])) {
+            case 'K':
+                $multiplier = 1024;
+                break;
+            case 'M':
+                $multiplier = 1024 ** 2;
+                break;
+            case 'G':
+                $multiplier = 1024 ** 3;
+                break;
+            default:
+                $multiplier = 1;
+                break;
+        }
+
+        return $base * $multiplier;
+    }
 }
diff --git a/test/php/library/Icinga/Util/EnvironmentTest.php b/test/php/library/Icinga/Util/EnvironmentTest.php
new file mode 100644
index 000000000..5f4c8aedf
--- /dev/null
+++ b/test/php/library/Icinga/Util/EnvironmentTest.php
@@ -0,0 +1,43 @@
+<?php
+/* Icinga Web 2 | (c) 2018 Icinga Development Team | GPLv2+ */
+
+namespace Tests\Icinga\Util;
+
+use Icinga\Util\Environment;
+use Icinga\Test\BaseTestCase;
+
+class EnvironmentTest extends BaseTestCase
+{
+    public function testRaiseMemoryLimit()
+    {
+        // set a low limit
+        ini_set('memory_limit', '128M');
+
+        Environment::raiseMemoryLimit('512M');
+        $this->assertEquals('536870912' /* 512M */, ini_get('memory_limit'));
+
+        Environment::raiseMemoryLimit('1G');
+        $this->assertEquals('1073741824' /* 1G */, ini_get('memory_limit'));
+
+        Environment::raiseMemoryLimit('512M');
+        $this->assertEquals('1073741824' /* 1G */, ini_get('memory_limit'));
+
+        // in phpunit usually there is no limit
+        ini_set('memory_limit', '-1');
+    }
+
+    public function testRaiseExecutionTime()
+    {
+        Environment::raiseExecutionTime(300);
+        $this->assertEquals(300, ini_get('max_execution_time'));
+
+        Environment::raiseExecutionTime(600);
+        $this->assertEquals(600, ini_get('max_execution_time'));
+
+        Environment::raiseExecutionTime(300);
+        $this->assertEquals(600, ini_get('max_execution_time'));
+
+        // in phpunit usually there is no limit
+        ini_set('max_execution_time', '0');
+    }
+}