Performance Improvement: Database Query Log Memory Optimization

src/Illuminate/Database/Connection.php

@@ -154,6 +154,13 @@ class Connection implements ConnectionInterface
      */
     protected $queryLog = [];
 
+    /**
+     * The maximum number of queries to keep in the query log.
+     *
+     * @var int
+     */
+    protected $maxQueryLogSize = 1000;
+
     /**
      * Indicates whether queries are being logged.
      *
@@ -858,6 +865,10 @@ public function logQuery($query, $bindings, $time = null)
 
         if ($this->loggingQueries) {
             $this->queryLog[] = compact('query', 'bindings', 'time');
+
+            if (count($this->queryLog) > $this->maxQueryLogSize) {
+                $this->queryLog = array_slice($this->queryLog, -$this->maxQueryLogSize, $this->maxQueryLogSize, false);
+            }
         }
     }
 
@@ -1569,6 +1580,29 @@ public function logging()
         return $this->loggingQueries;
     }
 
+    /**
+     * Set the maximum query log size.
+     *
+     * @param  int  $size
+     * @return $this
+     */
+    public function setMaxQueryLogSize(int $size)
+    {
+        $this->maxQueryLogSize = max(1, $size);
+
+        return $this;
+    }
+
+    /**
+     * Get the maximum query log size.
+     *
+     * @return int
+     */
+    public function getMaxQueryLogSize()
+    {
+        return $this->maxQueryLogSize;
+    }
+
     /**
      * Get the name of the connected database.
      *

tests/Database/DatabaseConnectionTest.php

@@ -549,6 +549,37 @@ protected function getMockConnection($methods = [], $pdo = null)
 
         return $connection;
     }
+
+    public function testQueryLogSizeLimit()
+    {
+        $connection = $this->getMockConnection();
+        $connection->enableQueryLog();
+        $connection->setMaxQueryLogSize(3);
+
+        $this->assertEquals(3, $connection->getMaxQueryLogSize());
+
+        for ($i = 0; $i < 5; $i++) {
+            $connection->logQuery('SELECT * FROM test WHERE id = ?', [$i], 10.0);
+        }
+
+        $queryLog = $connection->getQueryLog();
+
+        $this->assertCount(3, $queryLog);
+        $this->assertEquals([2], $queryLog[0]['bindings']);
+        $this->assertEquals([3], $queryLog[1]['bindings']);
+        $this->assertEquals([4], $queryLog[2]['bindings']);
+    }
+
+    public function testQueryLogSizeLimitMinimumValue()
+    {
+        $connection = $this->getMockConnection();
+
+        $connection->setMaxQueryLogSize(0);
+        $this->assertEquals(1, $connection->getMaxQueryLogSize());
+
+        $connection->setMaxQueryLogSize(-5);
+        $this->assertEquals(1, $connection->getMaxQueryLogSize());
+    }
 }
 
 class DatabaseConnectionTestMockPDO extends PDO