php－cli 下内存占用过大

写一个php脚本 希望把几个表内的数据通过查询写入一个指定表内，执行次数量大，大致有10W左右，每次循环查询语句有5个，写入是批量写入，每有100条写一次

运行中，无用的变量数据都有置空为null

现在就是php脚本运行过程中，占用内存一直变大，直至耗尽内存


用浏览器页面运行发现占用内存竟然小于php-cli命令行执行

现在问题：
1、php脚本运行过程中，释放内存，置空null后，还是需要gc来操作（这个是操作系统执行？），sql每次查询后，使用查询结果后，释放查询结果，目前内存依然是越来越大.

2、php命令行执行要比页面执行脚本耗内存吗

public function makeIndustryCacheByDayCli() {



        ini_set("memory_limit","-1");

        ignore_user_abort(true);

        set_time_limit(0);

        ob_end_clean();



        if ($_GET['argc'] > 0) {

            //检测时间段是否包含已处理的时间

            $m = M('CacheTime');

            $start_time = $m->where('`type`=4')->order('`end_time` DESC')->getField('`end_time`');



            echo "开始执行\n";

            //ob_flush();

            flush();



            //命令行执行

            $end_time = strtotime(date('Y-m-d', time()));



            //所有行业

            $industry = $this->_getIndustryTop();

            //所有来源站点

            $sites = $this->_getSourceSite();

            echo "时间：".date('Y-m-d', $start_time)."-".date('Y-m-d', $end_time)."开始执行\n";

            //ob_flush();

            flush();

            Log::write("时间：".date('Y-m-d', $start_time)."-".date('Y-m-d', $end_time)." 开始执行>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n\n", 'industryByDay缓存日志', 3, LOG_PATH.date('y_m_d').'.industryByDay.log');

            $server_m = new ServerModel();

            $mm = M();

            $log_num = 0;

            //时间循环 按天

            for ($t = $start_time; $t < $end_time; $t += 86400) {

                $start_time_inner = $t;

                $end_time_inner = $t+86400;

                //插入时间段表

                $cache_time_data['type'] = 4;

                $cache_time_data['start_time'] = $start_time_inner;

                $cache_time_data['end_time'] = $end_time_inner;

                $cache_time_data['time_name'] = date('Y年m月d日', $start_time_inner);

                $cache_time_data['status_industry'] = 1;

                $m->add($cache_time_data);



                echo "时间：".date('Y-m-d', $start_time_inner)." 一天内的数据 开始生成\n";

                //ob_flush();

                flush();



                $data = array();

                $where_common = " pubtime_stamp >= ".$start_time_inner

                    ." AND pubtime_stamp < ".$end_time_inner

                    ." AND is_similar = 0 AND sentiment_status = 1";



                //顶层行业循环

                foreach ($industry as $v_industry) {

                    //缓存表名称

                    $cache_table_name = 'cache_industry_day_' . $v_industry['table_suffix'];

                    //评论数据来源数据库

                    $dbconfig = $server_m->getDataServerInfoById($v_industry['server_id']);



                    $mm->db(1, $dbconfig);

                    $data_num = 0;

                    //所有具体行业

                    $industry_detail = $this->_getIndustry($v_industry['id'], 0);

                    //外层循环来源站点 内层循环行业 写入缓存表

                    foreach ($sites as $v_site) {

                        if ($v_site['id'] != '0' && $v_site['flag'] != '0') {

                            $where_site = " AND content_type = ".$v_site['flag']

                                ." AND site_id = ".$v_site['id'];

                        } elseif ($v_site['id'] == '0' && $v_site['flag'] != '0') {

                            $where_site = " AND content_type = ".$v_site['flag'];

                        } else {

                            $where_site = '';

                        }

                        foreach ($industry_detail as $v_industry_detail) {



                            $where_industry = " AND industry_level_".$v_industry_detail['level']

                                ." = ".$v_industry_detail['id'];



                            $where = $where_common . $where_site . $where_industry;



                            $where_good = $where." AND sentiment_value > 0";

                            $where_neuter = $where." AND sentiment_value = 0";

                            $where_bad = $where." AND sentiment_value < 0";



                            $data[$data_num]['source_id'] = $v_site['id'];

                            $data[$data_num]['source_type'] = $v_site['flag'];

                            $data[$data_num]['industry_id'] = $v_industry_detail['id'];

                            $data[$data_num]['date_day'] = $start_time_inner;

                            $data[$data_num]['comment_total_num'] = $mm->table('industry_data_keywords_map')

                                    ->where($where)

                                    ->count()/$v_industry_detail['keyword_num'];

                            $data[$data_num]['comment_good_num'] = $mm->table('industry_data_keywords_map')

                                    ->where($where_good)

                                    ->count()/$v_industry_detail['keyword_num'];

                            $data[$data_num]['comment_neuter_num'] = $mm->table('industry_data_keywords_map')

                                    ->where($where_neuter)

                                    ->count()/$v_industry_detail['keyword_num'];

                            $data[$data_num]['comment_bad_num'] = $mm->table('industry_data_keywords_map')

                                    ->where($where_bad)

                                    ->count()/$v_industry_detail['keyword_num'];

                            $data[$data_num]['comment_score'] = $mm->table('industry_data_keywords_map')

                                    ->where($where)

                                    ->avg('sentiment_value');



                            //输出信息 记录日志

                            $log_num++;

                            $data_num++;



                            echo $log_num .' 行业：'.$v_industry['name'].' 来源站点：'.$v_site['name'].' 具体行业：'. $v_industry_detail['name'].' 缓存数据生成'."\n";

                            //ob_flush();

                            flush();



                            Log::write($log_num .' 行业：'.$v_industry['name'].' 来源站点：'.$v_site['name'].' 具体行业：'. $v_industry_detail['name'].' 缓存数据生成', 'industryByDay缓存日志', 3, LOG_PATH.date('y_m_d').'.industryByDay.log');



                            //写入数据库

                            if ($data_num%4 == 0) {

                                $mm->table($cache_table_name)->addAll($data);

                                $data = null;

                                $data_num = 0;

                            }

                        }

                    }

                    if ($data) {

                        $mm->table($cache_table_name)->addAll($data);

                        $data = null;

                    }

                }

                echo "时间：".date('Y-m-d', $start_time_inner)." 一天内的数据 开始结束\n";

                //ob_flush();

                flush();

            }



            Log::write("时间：".date('Y-m-d', $start_time)."-".date('Y-m-d', $end_time)." 一共{$log_num}条数据生成结束!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!\n\n", 'industryByDay缓存日志', 3, LOG_PATH.date('y_m_d').'.industryByDay.log');



            echo "一共{$log_num}条缓存数据生成！\n";



        }

    }