我正在使用APC将类名映射存储到类文件路径.我在自动加载功能中构建这样的地图:
$class_paths = apc_fetch('class_paths');
// If the class path is stored in application cache - search finished.
if (isset($class_paths[$class])) {
return require_once $class_paths[$class];
// Otherwise search in known places
} else {
// List of places to look for class
$paths = array(
'/src/',
'/modules/',
'/libs/',
);
// Search directories and store path in cache if found.
foreach ($paths as $path) {
$file = DOC_ROOT . $path . $class . '.php';
if (file_exists($file)) {
echo 'File was found in => ' . $file . '<br />';
$class_paths[$class] = $file;
apc_store('class_paths', $class_paths);
return require_once $file;
}
}
}
我可以看到,随着越来越多的类被加载,它们被添加到地图中,但在某些时候apc_fetch返回NULL页面请求的中间,而不是返回地图.
Getting => class_paths
Array
(
[MCS\CMS\Helper\LayoutHelper] => /Users/mbl/Documents/Projects/mcs_ibob/core/trunk/src/MCS/CMS/Helper/LayoutHelper.php
[MCS\CMS\Model\Spot] => /Users/mbl/Documents/Projects/mcs_ibob/core/trunk/src/MCS/CMS/Model/Spot.php
)
Getting => class_paths
{null}
很多时候,缓存的值也会在页面请求之间消失.
这可能是什么原因？
我正在使用APC作为运行PHP 5.3的扩展(PECL).
更新: 在下面的评论中,您将看到人们声明APC不是持久性的,并且它不被信任.但在我的情况下,代码在15-50ms之间的一个页面请求中执行.我不应该长久相信 APC吗？
更新:
似乎缓存包含具有相同密钥的多个条目,当它应该只包含一个时 - 在调用时会覆盖该值apc_store().我希望这可以帮助别人理解这个问题.(我已禁用强力防守并写锁定)
Array
(
[num_slots] => 4099
[ttl] => 0
[num_hits] => 0
[num_misses] => 3
[num_inserts] => 9678
[expunges] => 0
[start_time] => 1293109072
[mem_size] => 40064
[num_entries] => 8
[file_upload_progress] => 1
[memory_type] => mmap
[locking_type] => file
[cache_list] => Array
(
[0] => Array
(
[info] => fSchema::mysql::fORM::default::/Users/mbl/Documents/Projects/mcs_ibob/core/trunk/public_html/::::column_info
[ttl] => 0
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 12456
)
[1] => Array
(
[info] => mcs:odk:class_paths
[ttl] => 3600
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 648
)
[2] => Array
(
[info] => mcs:odk:class_paths
[ttl] => 3600
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 648
)
[3] => Array
(
[info] => mcs:odk:class_paths
[ttl] => 3600
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 648
)
[4] => Array
(
[info] => mcs:odk:class_paths
[ttl] => 3600
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 648
)
[5] => Array
(
[info] => mcs:odk:class_paths
[ttl] => 3600
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 648
)
[6] => Array
(
[info] => mcs:odk:class_paths
[ttl] => 3600
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 648
)
[7] => Array
(
[info] => fSchema::mysql::fORM::default::/Users/mbl/Documents/Projects/mcs_ibob/core/trunk/public_html/::::merged_column_info
[ttl] => 0
[type] => user
[num_hits] => 0
[mtime] => 1293109072
[creation_time] => 1293109072
[deletion_time] => 0
[access_time] => 1293109072
[ref_count] => 0
[mem_size] => 23720
)
)
[deleted_list] => Array
(
)
)
它不是持久存储.您可以通过增加APC的内存大小来改进它,但无论如何,没有任何保证.因此,如果您看到它们被丢弃,您应该重新启动它们.