共享記憶體計數的時候沒有鎖定，會造成少量的更新遺失，不過對整體來說，遺失的資料量沒有大的影響。
<?php
/***
** 每個程序都單獨連線資料庫
* */
//configruation parameters
$tbl_id = 0;
$count_per_process = 10;
$concurrents = 100;
$logpath = "/tmp/s.log";
$host = "10.218.26.75";
$user = "user";
$pwd = "pwd";
$db = "test";
$port = 3306;
$sep = 1000;
$uid_count = 100000;
$uid_path= 100000;
if ($argc != 13) else
$uid_count = $uid_count / $concurrents;
}$shm_key = ftok(__file__, 't');
$shm_id = shmop_open($shm_key, "c", 0644, 100);
shmop_write($shm_id, 0, 0);
$m_start= microtime(true);
$conf = array(
'count' => $count_per_process,
'host' => $host,
'user' => $user,
'pwd' => $pwd,
'db' => $db,
'port' => $port,
'logpath' => $logpath,
'shm_id' => $shm_id,
'tbl_id' => $tbl_id,
'sep' => $sep,
'uid_count' => $uid_count,
'uid_path' => $uid_path,
);error_log("+++++++++++++++++++++begin++++++++++++++++\n",3,$logpath);
error_log("$m_start\n",3,$logpath);
for ($i = 1; $i <= $concurrents; ++$i)
}//main process
while (pcntl_waitpid(0, $status) != -1)
$m_end = microtime(true);
$m_duration = $m_end - $m_start;
echo "total time consumes:".$m_duration."\n";
$shm_size = shmop_size($shm_id);
$counter_str= shmop_read($shm_id, 0, $shm_size);
echo "shm counter :$counter_str\n";
$e =(int)$count_per_process * (int)$concurrents;
echo "theory counter :$e \n";
if (!shmop_delete($shm_id))
shmop_close($shm_id);
error_log("$m_end\n",3,$logpath);
error_log("+++++++++++++++++++++end++++++++++++++++\n",3,$logpath);
class simulator else
$this->domain_size = count($this->domains)-1;
$this->count = $conf['count'];
$this->sep = (int)$conf['sep'];
$this->shm_id = $conf['shm_id'];
$this->logpath = $conf['logpath'];
$this->uid_path = $conf['uid_path'];
$this->uid_count = (int)$conf['uid_count'];
$this->uid_is_ok = false; //關鍵字
$this->uid_tmp_count = 0; //
$this->link = mysql_connect($conf['host'].":".$conf['port'],$conf['user'],$conf['pwd']);
if(!$this->link)
$db_selected = mysql_select_db($conf['db'],$this->link);
if(!$db_selected)
}function __destruct()
if($this->uid_is_ok)
$contents .= $uid."\n";
}fwrite($fp,$contents);
fclose($fp);}}
}private function inc()
shmop_write($this->shm_id, $c, 0);
}public function execute() (uid,name,email) values ($uid,'$name','$email')";
$result = mysql_query($sql,$this->link);
$this->inc();
if(!$result)
}$end = microtime(true);
$duration = $end - $start;
//$line = "process ".$this->pid." ".$count." ".$duration."\n";
//echo "$line";
// error_log($line,3,$this->logpath);
}private function getemail()
private function getname()
private function getuid() else
return $uid;}}
}?>
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