进程锁定问题分析研究

<?php
/**
* 进行写锁定的测试
* 打开线程1
*/
require("file_lock.php");
$lock = new File_Lock(dirname(dirname(__FILE__)) . "/FileLock.lock");
/** 单个线程锁定的速度 1s 钟 3万次。 **/
/** 两个线程写，两万的数据 大概要 7s 钟*/
/** 一个线程写，一万的数据 大概要 3.9s 钟，居然两个文件同时写，要快一点*/
/** 不进行锁定，一个进程 写大概要 2.8s 钟，加锁是有代价的。 */
/** 不进行锁定，两个进程 分布不是很均匀，而且大多数都冲突 */
$lock->writeLock();
$lock->increment();
$lock->unlock();
while ($lock->get() < 2) {
usleep(1000);
}
sleep(1);
echo "begin to runing n";
$t1 = microtime(true);
for ($i = 0; $i < 10000; $i++)
{
$lock->writeLock();
$lock->increment(1);
$lock->unlock();
}
$t2 = microtime(true) - $t1;
echo $t2;
?>

<?php
class File_Lock
{
private $name;
private $handle;
private $mode;
function __construct($filename, $mode = 'a+b')
{
global $php_errormsg;
$this->name = $filename;
$path = dirname($this->name);
if ($path == '.' || !is_dir($path)) {
global $config_file_lock_path;
$this->name = str_replace(array("/", "\"), array("_", "_"), $this->name);
if ($config_file_lock_path == null) {
$this->name = dirname(__FILE__) . "/lock/" . $this->name;
} else {
$this->name = $config_file_lock_path . "/" . $this->name;
}
}
$this->mode = $mode;
$this->handle = @fopen($this->name, $mode);
if ($this->handle == false) {
throw new Exception($php_errormsg);
}
}
public function close()
{
if ($this->handle !== null ) {
@fclose($this->handle);
$this->handle = null;
}
}
public function __destruct()
{
$this->close();
}
public function lock($lockType, $nonBlockingLock = false)
{
if ($nonBlockingLock) {
return flock($this->handle, $lockType | LOCK_NB);
} else {
return flock($this->handle, $lockType);
}
}
public function readLock()
{
return $this->lock(LOCK_SH);
}
public function writeLock($wait = 0.1)
{
$startTime = microtime(true);
$canWrite = false;
do {
$canWrite = flock($this->handle, LOCK_EX);
if(!$canWrite) {
usleep(rand(10, 1000));
}
} while ((!$canWrite) && ((microtime(true) - $startTime) < $wait));
}
/**
* if you want't to log the number under multi-thread system,
* please open the lock, use a+ mod. then fopen the file will not
* destroy the data.
*
* this function increment a delt value , and save to the file.
*
* @param int $delt
* @return int
*/
public function increment($delt = 1)
{
$n = $this->get();
$n += $delt;
$this->set($n);
return $n;
}
public function get()
{
fseek($this->handle, 0);
return (int)fgets($this->handle);
}
public function set($value)
{
ftruncate($this->handle, 0);
return fwrite($this->handle, (string)$value);
}
public function unlock()
{
if ($this->handle !== null ) {
return flock($this->handle, LOCK_UN);
} else {
return true;
}
}
}
?>

class Memcache_Queue
{
private $memcache;
private $name;
private $prefix;
function __construct($maxSize, $name, $memcache, $prefix = "__memcache_queue__")
{
if ($memcache == null) {
throw new Exception("memcache object is null, new the object first.");
}
$this->memcache = $memcache;
$this->name = $name;
$this->prefix = $prefix;
$this->maxSize = $maxSize;
$this->front = 0;
$this->real = 0;
$this->size = 0;
}
function __get($name)
{
return $this->get($name);
}
function __set($name, $value)
{
$this->add($name, $value);
return $this;
}
function isEmpty()
{
return $this->size == 0;
}
function isFull()
{
return $this->size == $this->maxSize;
}
function enQueue($data)
{
if ($this->isFull()) {
throw new Exception("Queue is Full");
}
$this->increment("size");
$this->set($this->real, $data);
$this->set("real", ($this->real + 1) % $this->maxSize);
return $this;
}
function deQueue()
{
if ($this->isEmpty()) {
throw new Exception("Queue is Empty");
}
$this->decrement("size");
$this->delete($this->front);
$this->set("front", ($this->front + 1) % $this->maxSize);
return $this;
}
function getTop()
{
return $this->get($this->front);
}
function getAll()
{
return $this->getPage();
}
function getPage($offset = 0, $limit = 0)
{
if ($this->isEmpty() || $this->size < $offset) {
return null;
}
$keys[] = $this->getKeyByPos(($this->front + $offset) % $this->maxSize);
$num = 1;
for ($pos = ($this->front + $offset + 1) % $this->maxSize; $pos != $this->real; $pos = ($pos + 1) % $this->maxSize)
{
$keys[] = $this->getKeyByPos($pos);
$num++;
if ($limit > 0 && $limit == $num) {
break;
}
}
return array_values($this->memcache->get($keys));
}
function makeEmpty()
{
$keys = $this->getAllKeys();
foreach ($keys as $value) {
$this->delete($value);
}
$this->delete("real");
$this->delete("front");
$this->delete("size");
$this->delete("maxSize");
}
private function getAllKeys()
{
if ($this->isEmpty())
{
return array();
}
$keys[] = $this->getKeyByPos($this->front);
for ($pos = ($this->front + 1) % $this->maxSize; $pos != $this->real; $pos = ($pos + 1) % $this->maxSize)
{
$keys[] = $this->getKeyByPos($pos);
}
return $keys;
}
private function add($pos, $data)
{
$this->memcache->add($this->getKeyByPos($pos), $data);
return $this;
}
private function increment($pos)
{
return $this->memcache->increment($this->getKeyByPos($pos));
}
private function decrement($pos)
{
$this->memcache->decrement($this->getKeyByPos($pos));
}
private function set($pos, $data)
{
$this->memcache->set($this->getKeyByPos($pos), $data);
return $this;
}
private function get($pos)
{
return $this->memcache->get($this->getKeyByPos($pos));
}
private function delete($pos)
{
return $this->memcache->delete($this->getKeyByPos($pos));
}
private function getKeyByPos($pos)
{
return $this->prefix . $this->name . $pos;
}
}

php  google 风格分页代码
public function showCtrlPanel_g($halfPer = 5) {
  
  $re = '<div class="pageMore">
   <ul>
    <li><span>'.$this->lineCount.'条</span></li>
    <li><span>'.$this->currentPage.'/'.$this->pageCount.'页</span></li>';
  if($this->currentPage-$halfPer >1){
   $re .= '<li><a href="'.$this->fileName.'pageno=1"><span>1</span></a></li>';
   if($this->currentPage-$halfPer*2 >1){
    $re .= '<li><a href="'.$this->fileName.'pageno='.($this->currentPage-$halfPer*2).'"><span>...</span></a></li>';
   }else{
    $re .= '<li><a href="'.$this->fileName.'pageno=1"><span>...</span></a></li>';
   }
  }
  for ( $i = $this->currentPage - $halfPer,$i > 1 || $i = 1 , $j = $this->currentPage + $halfPer, $j < $this->pageCount || $j = $this->pageCount;$i <= $j ;$i++ )
  {
   $re .= $i ==  $this->currentPage
    ? '<li class="linkOn"><a href="'.$this->fileName.'pageno='.$i.'"><span>'.$i.'</span></a></li>'." "
    : '<li><a href="'.$this->fileName.'pageno='.$i.'"><span>'.$i.'</span></a></li>'." ";
  }
  if($this->currentPage+$halfPer < $this->pageCount){
   if($this->currentPage+$halfPer*2 < $this->pageCount){
    $re .= '<li><a href="'.$this->fileName.'pageno='.($this->currentPage+$halfPer*2).'"><span>...</span></a></li>';
   }else{
    $re .= '<li><a href="'.$this->fileName.'pageno='.$this->pageCount.'"><span>...</span></a></li>';
   }
   $re .= '<li><a href="'.$this->fileName.'pageno='.$this->pageCount.'"><span>'.$this->pageCount.'</span></a></li>';
  }
    
  $re .= ' 
   </ul>
  </div>';
  return $re;
 }

php 日期转换成日时截

private function toTimeStamp ($dateTimeString = NULL) {
  if (!$dateTimeString) {
   $dateTimeString = time();
  }
  $numeric = '';
  $add_space = false;
  for($i=0;$i<strlen($dateTimeString);$i++) {
   if(strpos('0123456789',$dateTimeString[$i])===false) {
    if($add_space) {
     $numeric .= ' ';
     $add_space = false;
    }
   } else {
    $numeric .= $dateTimeString[$i];
    $add_space = true;
   }
  }
  
  $numeric_array = explode(' ',$numeric,6);
  if(sizeof($numeric_array)<3 || ($numeric_array[0]==0 && $numeric_array[1]==0 && $numeric_array[2]==0)) {
   throw new Exception($dateTimeString . ' is an invalid parameter', 5);
  } else {
   $result = mktime(intval($numeric_array[3]), intval($numeric_array[4]), intval($numeric_array[5]),
        intval($numeric_array[1]), intval($numeric_array[2]), intval($numeric_array[0])) ;
  }
  
  return $result;
 
 }

class PageCache {

 /**
  * @var string $file 缓存文件地址
  * @access public
  */
 public $file;
 
 /**
  * @var int $cacheTime 缓存时间
  * @access public
  */
 public $cacheTime = 3600;
 
 /**
  * 构造函数
  * @param string $file 缓存文件地址
  * @param int $cacheTime 缓存时间
     */
 function __construct($file, $cacheTime = 3600) {
  $this->file = $file;
  $this->cacheTime = $cacheTime;
 }
 
 /**
  * 取缓存内容
  * @param bool 是否直接输出，true直接转到缓存页,false返回缓存内容
  * @return mixed
     */
 public function get($output = true) {
  if (is_file($this->file) && (time()-filemtime($this->file))<=$this->cacheTime && !$_GET['nocache']) {
   if ($output) {
    header('location:' . $this->file);
    exit;
   } else {
    return file_get_contents($this->file);
   }
  } else {
   return false;
  }
 }
 
 /**
  * 设置缓存内容
  * @param $content 内容html字符串
     */
 public function set($content) {
  $fp = fopen($this->file, 'w');
  fwrite($fp, $content);
  fclose($fp);
 }
}