function system_performance_settings

Form builder; Configure site performance settings.

See also

system_settings_form()

Related topics

File

modules/system/system.admin.inc, line 1281

Admin page callbacks for the system module.

Code

function system_performance_settings() {
  $description = '<p>' . t("The normal cache mode is suitable for most sites and does not cause any side effects. The aggressive cache mode causes Drupal to skip the loading (boot) and unloading (exit) of enabled modules when serving a cached page. This results in an additional performance boost but can cause unwanted side effects.") . '</p>';
  $problem_modules = array_unique(array_merge(module_implements('boot'), module_implements('exit')));
  sort($problem_modules);
  if (count($problem_modules) > 0) {
    $description .= '<p>' . t('<strong class="error">The following enabled modules are incompatible with aggressive mode caching and will not function properly: %modules</strong>', array(
      '%modules' => implode(', ', $problem_modules),
    )) . '.</p>';
  }
  else {
    $description .= '<p>' . t('<strong class="ok">Currently, all enabled modules are compatible with the aggressive caching policy.</strong> Please note, if you use aggressive caching and enable new modules, you will need to check this page again to ensure compatibility.') . '</p>';
  }
  $form['page_cache'] = array(
    '#type' => 'fieldset',
    '#title' => t('Page cache'),
    '#description' => t('Enabling the page cache will offer a significant performance boost. Drupal can store and send compressed cached pages requested by <em>anonymous</em> users. By caching a web page, Drupal does not have to construct the page each time it is viewed.'),
  );
  $form['page_cache']['cache'] = array(
    '#type' => 'radios',
    '#title' => t('Caching mode'),
    '#default_value' => variable_get('cache', CACHE_DISABLED),
    '#options' => array(
      CACHE_DISABLED => t('Disabled'),
      CACHE_NORMAL => t('Normal (recommended for production sites, no side effects)'),
      CACHE_AGGRESSIVE => t('Aggressive (experts only, possible side effects)'),
    ),
    '#description' => $description,
  );
  $period = drupal_map_assoc(array(
    0,
    60,
    180,
    300,
    600,
    900,
    1800,
    2700,
    3600,
    10800,
    21600,
    32400,
    43200,
    86400,
  ), 'format_interval');
  $period[0] = '<' . t('none') . '>';
  $form['page_cache']['cache_lifetime'] = array(
    '#type' => 'select',
    '#title' => t('Minimum cache lifetime'),
    '#default_value' => variable_get('cache_lifetime', 0),
    '#options' => $period,
    '#description' => t('On high-traffic sites, it may be necessary to enforce a minimum cache lifetime. The minimum cache lifetime is the minimum amount of time that will elapse before the cache is emptied and recreated, and is applied to both page and block caches. A larger minimum cache lifetime offers better performance, but users will not see new content for a longer period of time.'),
  );
  $form['page_cache']['page_compression'] = array(
    '#type' => 'radios',
    '#title' => t('Page compression'),
    '#default_value' => variable_get('page_compression', TRUE),
    '#options' => array(
      t('Disabled'),
      t('Enabled'),
    ),
    '#description' => t("By default, Drupal compresses the pages it caches in order to save bandwidth and improve download times. This option should be disabled when using a webserver that performs compression."),
  );
  $form['block_cache'] = array(
    '#type' => 'fieldset',
    '#title' => t('Block cache'),
    '#description' => t('Enabling the block cache can offer a performance increase for all users by preventing blocks from being reconstructed on each page load. If the page cache is also enabled, performance increases from enabling the block cache will mainly benefit authenticated users.'),
  );
  $form['block_cache']['block_cache'] = array(
    '#type' => 'radios',
    '#title' => t('Block cache'),
    '#default_value' => variable_get('block_cache', CACHE_DISABLED),
    '#options' => array(
      CACHE_DISABLED => t('Disabled'),
      CACHE_NORMAL => t('Enabled (recommended)'),
    ),
    '#disabled' => count(module_implements('node_grants')),
    '#description' => t('Note that block caching is inactive when modules defining content access restrictions are enabled.'),
  );
  $form['bandwidth_optimizations'] = array(
    '#type' => 'fieldset',
    '#title' => t('Bandwidth optimizations'),
    '#description' => t('<p>Drupal can automatically optimize external resources like CSS and JavaScript, which can reduce both the size and number of requests made to your website. CSS files can be aggregated and compressed into a single file, while JavaScript files are aggregated (but not compressed). These optional optimizations may reduce server load, bandwidth requirements, and page loading times.</p><p>These options are disabled if you have not set up your files directory, or if your download method is set to private.</p>'),
  );
  $directory = file_directory_path();
  $is_writable = is_dir($directory) && is_writable($directory) && variable_get('file_downloads', FILE_DOWNLOADS_PUBLIC) == FILE_DOWNLOADS_PUBLIC;
  $form['bandwidth_optimizations']['preprocess_css'] = array(
    '#type' => 'radios',
    '#title' => t('Optimize CSS files'),
    '#default_value' => intval(variable_get('preprocess_css', 0) && $is_writable),
    '#disabled' => !$is_writable,
    '#options' => array(
      t('Disabled'),
      t('Enabled'),
    ),
    '#description' => t('This option can interfere with theme development and should only be enabled in a production environment.'),
  );
  $form['bandwidth_optimizations']['preprocess_js'] = array(
    '#type' => 'radios',
    '#title' => t('Optimize JavaScript files'),
    '#default_value' => intval(variable_get('preprocess_js', 0) && $is_writable),
    '#disabled' => !$is_writable,
    '#options' => array(
      t('Disabled'),
      t('Enabled'),
    ),
    '#description' => t('This option can interfere with module development and should only be enabled in a production environment.'),
  );
  $form['clear_cache'] = array(
    '#type' => 'fieldset',
    '#title' => t('Clear cached data'),
    '#description' => t('Caching data improves performance, but may cause problems while troubleshooting new modules, themes, or translations, if outdated information has been cached. To refresh all cached data on your site, click the button below. <em>Warning: high-traffic sites will experience performance slowdowns while cached data is rebuilt.</em>'),
  );
  $form['clear_cache']['clear'] = array(
    '#type' => 'submit',
    '#value' => t('Clear cached data'),
    '#submit' => array(
      'system_clear_cache_submit',
    ),
  );
  $form['#submit'][] = 'drupal_clear_css_cache';
  $form['#submit'][] = 'drupal_clear_js_cache';
  return system_settings_form($form);
}