diff -u b/modules/redirect_404/redirect_404.module b/modules/redirect_404/redirect_404.module
--- b/modules/redirect_404/redirect_404.module
+++ b/modules/redirect_404/redirect_404.module
@@ -45,7 +45,7 @@
   // For row limit n, get the wid of the nth row in descending wid order.
   // Counting the most recent n rows avoids issues with wid number sequences,
   // e.g. auto_increment value > 1 or rows deleted directly from the table.
-  if ($row_limit > 0) {
+  /*if ($row_limit > 0) {
     $query = \Drupal::database()->select('redirect_404', 'r404')
       ->extend('Drupal\Core\Database\Query\TableSortExtender')
       ->orderBy('timestamp', 'DESC')
@@ -60,7 +60,7 @@
         ->condition('timestamp', $query, '<')
         ->execute();
     }
-  }
+  }*/
 }
 
 /**
diff -u b/modules/redirect_404/src/RedirectNotFoundStorage.php b/modules/redirect_404/src/RedirectNotFoundStorage.php
--- b/modules/redirect_404/src/RedirectNotFoundStorage.php
+++ b/modules/redirect_404/src/RedirectNotFoundStorage.php
@@ -74,24 +74,18 @@
     // Cleanup the redirect_404 table.
     $row_limit = \Drupal::config('redirect_404.settings')->get('row_limit');
 
-    // For row limit n, get the wid of the nth row in descending wid order.
-    // Counting the most recent n rows avoids issues with wid number sequences,
-    // e.g. auto_increment value > 1 or rows deleted directly from the table.
-    $query = $this->database->select('redirect_404', 'r404');
-    //$query->fields('r404');
-    $query->addExpression('pow(2, -(UNIX_TIMESTAMP(NOW()) - timestamp)/86400)', 'boh');
-    //$query->condition('relevancy', 0.99, '>');
-    $query->orderBy('boh', 'DESC');
-
-    $query->fields('r404');
-    $query->condition('relevancy', 0.99, '>');
-    $result = $query->execute()->fetchAll();
-
-    if ($result) {
-      $delete = $this->database->select('redirect_404', 'r404');
-      $delete->condition('path', $result, 'NOT IN');
-      $result = $delete->execute()->fetchAll();
-    }
+
+    // Determine cutoff level.
+    $select = $this->database->query('SELECT path, langcode, (relevancy * pow(2, -(UNIX_TIMESTAMP(NOW()) - timestamp)/' . $this->halflife . ')) as cutoff FROM {redirect_404} ORDER BY (relevancy * pow(2, -(UNIX_TIMESTAMP(NOW()) - timestamp)/' . $this->halflife . ')) DESC LIMIT ' . $row_limit . ', 1')->fetchObject();
+
+    // Delete records below cutoff.
+    $delete = $this->database->query('DELETE FROM {redirect_404} WHERE (relevancy * pow(2, -(UNIX_TIMESTAMP(NOW()) - timestamp)/' . $this->halflife . ')) < :cutoff', [':cutoff' => $select->cutoff]);
+
+
+    //$result = $result->cutoff;
+    $result['select'] = $select->cutoff;
+    $result['delete'] = $delete;
+
 
     return $result;
   }