这段代码总是在2m左右出现504 Proxy Timeout异常，什么原因

function autonewnewegg($arr){<br>
            $fucknum=intval($arr['fucknum']);  // # 获取抓取条数的整数值<br>
            $outime=$fucknum*2+100;<br>
            set_time_limit($outime);//设置脚本执行时间<br>
            $nextnum=20;//连续查找10次不存在则终止<br>
            $sn=$arr['sn'];<br>
            <br>
            $acl=explode("-",$sn);<br>
            $acl_1=preg_replace('/[^0-9]+/','',$acl[1]);        //二次<br>
            $a=$b=0;                                            //二次<br>
            <br>
            while($fucknum>0){<br>
                $arr1 = $arr2 = array();<br>
                if($acl[2]
                    $acl[2]=str_pad("$acl[2]",3,'0',STR_PAD_LEFT);<br>
                    $acl_1=str_pad("$acl_1",2,'0',STR_PAD_LEFT);<br>
                    $acl[1]="c".$acl_1;<br>
                    $arr_in=implode("-",$acl);<br>
            <br>
                    $url=$GLOBALS['competitor'][1]['product'].$arr_in.'.htm';<br>
                    if($acl[2]==999){<br>
                        $acl_1=$acl_1+1;<br>
                        $acl[2]=001;<br>
                    }else {<br>
                        ++$acl[2];<br>
                    }<br>
                }elseif($acl[0]
                    $acl[0]=str_pad("$acl[0]",2,'0',STR_PAD_LEFT); <div class="clear">
                 
              
              
        
            </div>