我们都知道一个文件夹文件不宜过多，文件过多，会导致性能下降，那到底怎样算过多呢？
今天板子决定蹂躏下自己的新mac
因本文旨在讨论相同状态下，性能随单目录文件数量变化而发生的变化，所以未做其他特别设置
准备：
Mac Pro （ssd）一台 (安装ubuntu 12.04 虚拟机 LNMP 环境)
5个文件夹，各分别包含1w、5w、10w、50w、100w个同样内容小文件
压测命令：ab -n 10000 -c 100 ‘http://s1.localhost.com/files.php?num=xxx’
files.php：
$num = empty($_GET['num']) ? 10000 : $_GET['num'];
echo file_get_contents("/..filepath../$num/file_".rand(1,$num));
以下是测试结果：
有个小需求，批量分析一批pdf文件的总页数，写（找）了个小函数，如下：
function getPageTotal($path){
if (!$fp = @fopen($path, 'r')) {
return false;
}
$max=0;
while(!feof($fp)) {
$line = fgets($fp,255);
if (preg_match('/\/Count [0-9]+/', $line, $matches)){
preg_match('/[0-9]+/',$matches[0], $matches2);
if ($max<$matches2[0]) $max=$matches2[0];
}
}
fclose($fp);
return $max;
}
实际使用中，发现有极个别文件识别失败，取样分析后，发现出问题的文件都是mac格式的，那自然就是fgets对mac换行符的识别问题了
查了下手册: fgets
Note: If PHP is not properly recognizing the line endings when reading files either on or created by a Macintosh computer, enabling the auto_detect_line_endings run-time configuration option may help resolve the problem.
auto_detect_line_endings 这个运行时配置到是从没注意过，ok、稍作修改
function getPageTotal($path){
ini_set("auto_detect_line_endings",true);
if (!$fp = @fopen($path, 'r')) {
return false;
}
$max=0;
while(!feof($fp)) {
$line = fgets($fp,255);
if (preg_match('/\/Count [0-9]+/', $line, $matches)){
preg_match('/[0-9]+/',$matches[0], $matches2);
if ($max<$matches2[0]) $max=$matches2[0];
}
}
fclose($fp);
return $max;
}
问题解决！
关于auto-detect-line-endings的解释：
When turned on, PHP will examine the data read by fgets() and file() to see if it is using Unix, MS-Dos or Macintosh line-ending conventions.
This enables PHP to interoperate with Macintosh systems, but defaults to Off, as there is a very small performance penalty when detecting the EOL conventions for the first line, and also because people using carriage-returns as item separators under Unix systems would experience non-backwards-compatible behaviour.
Note: This configuration option was introduced in PHP 4.3.0