- Patch #561990 by catch, mikeytown2, nnewton: avoid variable_set() and variable_del() stampedes.

merge-requests/26/head
Dries Buytaert 2010-06-24 18:56:10 +00:00
parent 41abf46f07
commit 42a86ff32d
1 changed files with 20 additions and 7 deletions

View File

@ -743,13 +743,26 @@ function drupal_get_filename($type, $name, $filename = NULL) {
* file.
*/
function variable_initialize($conf = array()) {
// NOTE: caching the variables improves performance by 20% when serving cached pages.
// NOTE: caching the variables improves performance by 20% when serving
// cached pages.
if ($cached = cache_get('variables', 'cache_bootstrap')) {
$variables = $cached->data;
}
else {
$variables = array_map('unserialize', db_query('SELECT name, value FROM {variable}')->fetchAllKeyed());
cache_set('variables', $variables, 'cache_bootstrap');
// Cache miss. Avoid a stampede.
$name = 'variable_init';
if (!lock_acquire($name, 1)) {
// Another request is building the variable cache.
// Wait, then re-run this function.
lock_wait($name);
return variable_initialize($conf);
}
else {
// Proceed with variable rebuild.
$variables = array_map('unserialize', db_query('SELECT name, value FROM {variable}')->fetchAllKeyed());
cache_set('variables', $variables, 'cache_bootstrap');
lock_release($name);
}
}
foreach ($conf as $name => $value) {
@ -2169,6 +2182,10 @@ function _drupal_bootstrap_database() {
function _drupal_bootstrap_variables() {
global $conf;
// Initialize the lock system.
require_once DRUPAL_ROOT . '/' . variable_get('lock_inc', 'includes/lock.inc');
lock_initialize();
// Load variables from the database, but do not overwrite variables set in settings.php.
$conf = variable_initialize(isset($conf) ? $conf : array());
// Load bootstrap modules.
@ -2182,10 +2199,6 @@ function _drupal_bootstrap_variables() {
function _drupal_bootstrap_page_header() {
bootstrap_invoke_all('boot');
// Prepare for non-cached page workflow.
require_once DRUPAL_ROOT . '/' . variable_get('lock_inc', 'includes/lock.inc');
lock_initialize();
if (!drupal_is_cli()) {
ob_start();
drupal_page_header();